2013-03-10 09:28:35 +00:00
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.\" Page by b.hubert
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2015-01-13 08:26:39 +00:00
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.\" and Copyright (C) 2015, Thomas Gleixner <tglx@linutronix.de>
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.\" and Copyright (C) 2015, Michael Kerrisk <mtk.manpages@gmail.com>
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ldd.1, capget.2, clone.2, create_module.2, fallocate.2, futex.2, get_kernel_syms.2, get_thread_area.2, getcpu.2, getitimer.2, getpid.2, io_cancel.2, io_destroy.2, io_getevents.2, io_setup.2, io_submit.2, ioctl_list.2, mkdir.2, mknod.2, pciconfig_read.2, pivot_root.2, posix_fadvise.2, query_module.2, sendfile.2, set_thread_area.2, setns.2, unshare.2, __setfpucw.3, a64l.3, addseverity.3, argz_add.3, bindresvport.3, cabs.3, cacos.3, cacosh.3, canonicalize_file_name.3, carg.3, casin.3, casinh.3, catan.3, catanh.3, ccos.3, ccosh.3, cerf.3, cexp.3, cexp2.3, cimag.3, clog.3, clog10.3, clog2.3, cmsg.3, conj.3, cpow.3, cproj.3, creal.3, csin.3, csinh.3, csqrt.3, ctan.3, ctanh.3, des_crypt.3, envz_add.3, fdim.3, fma.3, fmax.3, fmemopen.3, fmin.3, fmtmsg.3, fpclassify.3, gamma.3, getpt.3, getrpcent.3, getrpcport.3, getttyent.3, isgreater.3, key_setsecret.3, lgamma.3, malloc_hook.3, mempcpy.3, nan.3, netlink.3, nextafter.3, putgrent.3, remove.3, remquo.3, rpc.3, rtime.3, rtnetlink.3, setaliasent.3, setnetgrent.3, signbit.3, significand.3, sincos.3, stdin.3, tgamma.3, xcrypt.3, xdr.3, cciss.4, hpsa.4, mouse.4, pts.4, sk98lin.4, tty_ioctl.4, wavelan.4, hosts.equiv.5, rpc.5, tzfile.5, boot.7, complex.7, ddp.7, fifo.7, futex.7, icmp.7, ip.7, ipv6.7, netdevice.7, netlink.7, packet.7, raw.7, rtnetlink.7, socket.7, tcp.7, udp.7, unix.7, x25.7, sync.8: Global fix: Put copyright info at top of page, followed by blank line and LICENSE
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-03-10 09:29:51 +00:00
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.\"
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2013-03-10 09:29:11 +00:00
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.\" %%%LICENSE_START(FREELY_REDISTRIBUTABLE)
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2013-03-10 09:28:35 +00:00
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.\" may be freely modified and distributed
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epoll_create.2, epoll_ctl.2, epoll_wait.2, eventfd.2, fallocate.2, futex.2, getcpu.2, getitimer.2, ioctl_list.2, ioprio_set.2, migrate_pages.2, move_pages.2, pciconfig_read.2, sendfile.2, setns.2, signalfd.2, spu_create.2, spu_run.2, sysinfo.2, timerfd_create.2, backtrace.3, cmsg.3, error.3, getpt.3, getrpcent.3, getrpcport.3, getsubopt.3, offsetof.3, program_invocation_name.3, rpc.3, rpmatch.3, rtnetlink.3, xdr.3, cciss.4, hpsa.4, pts.4, charmap.5, dir_colors.5, elf.5, gai.conf.5, locale.5, nscd.conf.5, nss.5, resolv.conf.5, rpc.5, arp.7, cpuset.7, ddp.7, epoll.7, fifo.7, futex.7, icmp.7, ip.7, ipv6.7, mailaddr.7, netdevice.7, packet.7, raw.7, regex.7, rtnetlink.7, socket.7, spufs.7, tcp.7, udp.7, unix.7, x25.7, ldconfig.8, nscd.8: Global fix: s/END_LICENSE/LICENSE_END/
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-03-12 09:26:07 +00:00
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.\" %%%LICENSE_END
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2004-11-03 13:51:07 +00:00
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.\"
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.\" Niki A. Rahimi (LTC Security Development, narahimi@us.ibm.com)
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.\" added ERRORS section.
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.\"
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.\" Modified 2004-06-17 mtk
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.\" Modified 2004-10-07 aeb, added FUTEX_REQUEUE, FUTEX_CMP_REQUEUE
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.\"
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2007-04-12 22:42:49 +00:00
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.\" 2.6.18 adds (Ingo Molnar) priority inheritance support:
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.\" FUTEX_LOCK_PI, FUTEX_UNLOCK_PI, and FUTEX_TRYLOCK_PI. These need
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2006-09-26 06:38:06 +00:00
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.\" to be documented in the manual page. Probably there is sufficient
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.\" material in the kernel source file Documentation/pi-futex.txt.
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2013-02-25 07:20:07 +00:00
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.\" commit c87e2837be82df479a6bae9f155c43516d2feebc
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.\" Author: Ingo Molnar <mingo@elte.hu>
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.\" Date: Tue Jun 27 02:54:58 2006 -0700
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.\"
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.\" commit e2970f2fb6950183a34e8545faa093eb49d186e1
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.\" Author: Ingo Molnar <mingo@elte.hu>
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.\" Date: Tue Jun 27 02:54:47 2006 -0700
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.\"
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2014-05-14 08:36:23 +00:00
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.\" See Documentation/pi-futex.txt
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2013-02-25 07:20:07 +00:00
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.\"
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.\" 2.6.31 adds FUTEX_WAIT_REQUEUE_PI, FUTEX_CMP_REQUEUE_PI
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.\" commit 52400ba946759af28442dee6265c5c0180ac7122
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.\" Author: Darren Hart <dvhltc@us.ibm.com>
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.\" Date: Fri Apr 3 13:40:49 2009 -0700
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.\"
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.\" commit ba9c22f2c01cf5c88beed5a6b9e07d42e10bd358
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.\" Author: Darren Hart <dvhltc@us.ibm.com>
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.\" Date: Mon Apr 20 22:22:22 2009 -0700
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.\"
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.\" See Documentation/futex-requeue-pi.txt
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2006-09-26 06:38:06 +00:00
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.\"
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chown.2, fcntl.2, futex.2, recvmmsg.2, sched_setscheduler.2, semget.2, shmget.2, malloc.3, pthread_attr_setinheritsched.3, pthread_attr_setschedparam.3, pthread_attr_setschedpolicy.3, pthread_setaffinity_np.3, strcpy.3, capabilities.7, cpuset.7, credentials.7, pthreads.7: tstamp
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2014-05-21 11:15:30 +00:00
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.TH FUTEX 2 2014-05-21 "Linux" "Linux Programmer's Manual"
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2004-11-03 13:51:07 +00:00
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.SH NAME
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2012-10-21 06:19:01 +00:00
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futex \- fast user-space locking
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2004-11-03 13:51:07 +00:00
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.SH SYNOPSIS
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2006-08-04 09:41:28 +00:00
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.nf
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2004-11-03 13:51:07 +00:00
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.sp
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.B "#include <linux/futex.h>"
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.B "#include <sys/time.h>"
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.sp
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2015-01-12 14:40:43 +00:00
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.BI "int futex(int *" uaddr ", int " futex_op ", int " val ,
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.BI " const struct timespec *" timeout ,
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2006-08-04 09:41:28 +00:00
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.BI " int *" uaddr2 ", int " val3 );
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2004-11-03 13:51:07 +00:00
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.\" int *? void *? u32 *?
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2006-08-04 09:41:28 +00:00
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.fi
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2015-01-11 08:37:53 +00:00
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2014-05-15 04:45:22 +00:00
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.IR Note :
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There is no glibc wrapper for this system call; see NOTES.
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getent.1, intro.1, time.1, _exit.2, _syscall.2, accept.2, access.2, acct.2, adjtimex.2, alarm.2, alloc_hugepages.2, arch_prctl.2, bdflush.2, bind.2, brk.2, cacheflush.2, capget.2, chdir.2, chmod.2, chown.2, chroot.2, clock_getres.2, clock_nanosleep.2, clone.2, close.2, connect.2, create_module.2, delete_module.2, dup.2, epoll_create.2, epoll_ctl.2, epoll_wait.2, eventfd.2, execve.2, exit_group.2, faccessat.2, fchmodat.2, fchownat.2, fcntl.2, flock.2, fork.2, fstatat.2, fsync.2, futex.2, futimesat.2, get_kernel_syms.2, get_robust_list.2, get_thread_area.2, getcpu.2, getdents.2, getdomainname.2, getgid.2, getgroups.2, gethostname.2, getitimer.2, getpagesize.2, getpeername.2, getpid.2, getpriority.2, getresuid.2, getrlimit.2, getrusage.2, getsid.2, getsockname.2, getsockopt.2, gettid.2, gettimeofday.2, getuid.2, getunwind.2, getxattr.2, idle.2, init_module.2, inotify_add_watch.2, inotify_init.2, inotify_rm_watch.2, intro.2, io_cancel.2, io_destroy.2, io_getevents.2, io_setup.2, io_submit.2, ioctl.2, ioctl_list.2, ioperm.2, iopl.2, ioprio_set.2, ipc.2, kcmp.2, kill.2, killpg.2, link.2, linkat.2, listen.2, listxattr.2, llseek.2, lookup_dcookie.2, lseek.2, madvise.2, migrate_pages.2, mincore.2, mkdir.2, mkdirat.2, mknod.2, mknodat.2, mlock.2, mmap.2, mmap2.2, modify_ldt.2, mount.2, move_pages.2, mprotect.2, mq_getsetattr.2, mremap.2, msgctl.2, msgget.2, msgop.2, msync.2, nanosleep.2, nfsservctl.2, nice.2, open.2, openat.2, outb.2, pause.2, pciconfig_read.2, perf_event_open.2, perfmonctl.2, personality.2, pipe.2, pivot_root.2, poll.2, posix_fadvise.2, prctl.2, pread.2, process_vm_readv.2, ptrace.2, query_module.2, quotactl.2, read.2, readahead.2, readdir.2, readlink.2, readlinkat.2, readv.2, reboot.2, recv.2, remap_file_pages.2, removexattr.2, rename.2, renameat.2, rmdir.2, rt_sigqueueinfo.2, sched_get_priority_max.2, sched_rr_get_interval.2, sched_setaffinity.2, sched_setparam.2, sched_setscheduler.2, sched_yield.2, select.2, semctl.2, semget.2, semop.2, send.2, sendfile.2, set_thread_area.2, set_tid_address.2, seteuid.2, setfsgid.2, setfsuid.2, setgid.2, setpgid.2, setresuid.2, setreuid.2, setsid.2, setuid.2, setup.2, setxattr.2, shmctl.2, shmget.2, shmop.2, shutdown.2, sigaction.2, sigaltstack.2, signal.2, signalfd.2, sigpending.2, sigprocmask.2, sigreturn.2, sigsuspend.2, sigwaitinfo.2, socket.2, socketcall.2, socketpair.2, splice.2, stat.2, statfs.2, stime.2, swapon.2, symlink.2, symlinkat.2, sync.2, sync_file_range.2, sysctl.2, sysfs.2, sysinfo.2, syslog.2, tee.2, time.2, timerfd_create.2, times.2, tkill.2, truncate.2, umask.2, umount.2, uname.2, unimplemented.2, unlink.2, unlinkat.2, uselib.2, ustat.2, utime.2, utimensat.2, vfork.2, vhangup.2, vm86.2, vmsplice.2, wait.2, wait4.2, write.2, CPU_SET.3, INFINITY.3, MB_CUR_MAX.3, MB_LEN_MAX.3, __setfpucw.3, a64l.3, abort.3, abs.3, acos.3, acosh.3, addseverity.3, adjtime.3, aio_cancel.3, aio_error.3, aio_fsync.3, aio_read.3, aio_return.3, aio_suspend.3, aio_write.3, alloca.3, argz_add.3, asin.3, asinh.3, asprintf.3, assert.3, assert_perror.3, atan.3, atan2.3, atanh.3, atexit.3, atof.3, atoi.3, backtrace.3, basename.3, bcmp.3, bcopy.3, bindresvport.3, bsd_signal.3, bsearch.3, bstring.3, btowc.3, btree.3, byteorder.3, bzero.3, cabs.3, cacos.3, cacosh.3, canonicalize_file_name.3, carg.3, casin.3, casinh.3, catan.3, catanh.3, catgets.3, catopen.3, cbrt.3, ccos.3, ccosh.3, ceil.3, cerf.3, cexp.3, cexp2.3, cfree.3, cimag.3, clearenv.3, clock.3, clock_getcpuclockid.3, clog.3, clog10.3, clog2.3, closedir.3, cmsg.3, confstr.3, conj.3, copysign.3, cos.3, cosh.3, cpow.3, cproj.3, creal.3, crypt.3, csin.3, csinh.3, csqrt.3, ctan.3, ctanh.3, ctermid.3, ctime.3, daemon.3, dbopen.3, des_crypt.3, difftime.3, dirfd.3, div.3, dl_iterate_phdr.3, dlopen.3, dprintf.3, drand48.3, drand48_r.3, dysize.3, ecvt.3, ecvt_r.3, encrypt.3, end.3, endian.3, envz_add.3, erf.3, erfc.3, err.3, errno.3, error.3, ether_aton.3, euidaccess.3, exec.3, exit.3, exp.3, exp10.3, exp2.3, expm1.3, fabs.3, fclose.3, fcloseall.3, fdim.3, fenv.3, ferror.3, fexecve.3, fflush.3, ffs.3, fgetgrent.3, fgetpwent.3, fgetwc.3, fgetws.3, finite.3, flockfile.3, floor.3, fma.3, fmax.3, fmemopen.3, fmin.3, fmod.3, fmtmsg.3, fnmatch.3, fopen.3, fpathconf.3, fpclassify.3, fpurge.3, fputwc.3, fputws.3, fread.3, frexp.3, fseek.3, fseeko.3, ftime.3, ftok.3, fts.3, ftw.3, futimes.3, fwide.3, gamma.3, gcvt.3, getaddrinfo.3, getaddrinfo_a.3, getauxval.3, getcontext.3, getcwd.3, getdate.3, getdirentries.3, getdtablesize.3, getenv.3, getfsent.3, getgrent.3, getgrent_r.3, getgrnam.3, getgrouplist.3, gethostbyname.3, gethostid.3, getipnodebyname.3, getline.3, getloadavg.3, getlogin.3, getmntent.3, getnameinfo.3, getnetent.3, getnetent_r.3, getopt.3, getpass.3, getprotoent.3, getprotoent_r.3, getpt.3, getpw.3, getpwent.3, getpwent_r.3, getpwnam.3, getrpcent.3, getrpcent_r.3, getrpcport.3, gets.3, getservent.3, getservent_r.3, getspnam.3, getttyent.3, getumask.3, getusershell.3, getutent.3, getw.3, getwchar.3, glob.3, grantpt.3, gsignal.3, hash.3, hsearch.3, hypot.3, iconv.3, iconv_close.3, iconv_open.3, ilogb.3, index.3, inet.3, inet_ntop.3, inet_pton.3, infnan.3, initgroups.3, insque.3, intro.3, isalpha.3, isatty.3, isgreater.3, iswalnum.3, iswalpha.3, iswblank.3, iswcntrl.3, iswctype.3, iswdigit.3, iswgraph.3, iswlower.3, iswprint.3, iswpunct.3, iswspace.3, iswupper.3, iswxdigit.3, j0.3, key_setsecret.3, ldexp.3, lgamma.3, lio_listio.3, localeconv.3, lockf.3, log.3, log10.3, log1p.3, log2.3, logb.3, login.3, longjmp.3, lrint.3, lround.3, lsearch.3, lseek64.3, makecontext.3, makedev.3, malloc.3, malloc_hook.3, mblen.3, mbrlen.3, mbrtowc.3, mbsinit.3, mbsnrtowcs.3, mbsrtowcs.3, mbstowcs.3, mbtowc.3, memccpy.3, memchr.3, memcmp.3, memcpy.3, memfrob.3, memmem.3, memmove.3, mempcpy.3, memset.3, mkdtemp.3, mkfifo.3, mkfifoat.3, mkstemp.3, mktemp.3, modf.3, mpool.3, mq_close.3, mq_getattr.3, mq_notify.3, mq_open.3, mq_receive.3, mq_send.3, mq_unlink.3, mtrace.3, nan.3, netlink.3, nextafter.3, nl_langinfo.3, offsetof.3, on_exit.3, opendir.3, openpty.3, perror.3, popen.3, posix_fallocate.3, posix_memalign.3, posix_openpt.3, pow.3, pow10.3, printf.3, profil.3, program_invocation_name.3, psignal.3, pthread_kill_other_threads_np.3, ptsname.3, putenv.3, putgrent.3, putpwent.3, puts.3, putwchar.3, qecvt.3, qsort.3, queue.3, raise.3, rand.3, random.3, random_r.3, rcmd.3, re_comp.3, readdir.3, realpath.3, recno.3, regex.3, remainder.3, remove.3, remquo.3, resolver.3, rewinddir.3, rexec.3, rint.3, round.3, rpc.3, rpmatch.3, rtime.3, rtnetlink.3, scalb.3, scalbln.3, scandir.3, scandirat.3, scanf.3, seekdir.3, sem_close.3, sem_destroy.3, sem_getvalue.3, sem_init.3, sem_open.3, sem_post.3, sem_unlink.3, sem_wait.3, setaliasent.3, setbuf.3, setenv.3, setjmp.3, setlocale.3, setlogmask.3, setnetgrent.3, shm_open.3, siginterrupt.3, signbit.3, significand.3, sigpause.3, sigqueue.3, sigset.3, sigsetops.3, sigvec.3, sin.3, sincos.3, sinh.3, sleep.3, sockatmark.3, sqrt.3, statvfs.3, stdarg.3, stdin.3, stdio.3, stdio_ext.3, stpcpy.3, stpncpy.3, strcasecmp.3, strcat.3, strchr.3, strcmp.3, strcoll.3, strcpy.3, strdup.3, strerror.3, strfmon.3, strfry.3, strftime.3, string.3, strlen.3, strnlen.3, strpbrk.3, strptime.3, strsep.3, strsignal.3, strspn.3, strstr.3, strtod.3, strtoimax.3, strtok.3, strtol.3, strtoul.3, strverscmp.3, strxfrm.3, swab.3, sysconf.3, syslog.3, system.3, sysv_signal.3, tan.3, tanh.3, tcgetpgrp.3, tcgetsid.3, telldir.3, tempnam.3, termios.3, tgamma.3, timegm.3, timeradd.3, tmpfile.3, tmpnam.3, toascii.3, toupper.3, towctrans.3, towlower.3, towupper.3, trunc.3, tsearch.3, ttyname.3, ttyslot.3, tzset.3, ualarm.3, ulimit.3, ungetwc.3, unlocked_stdio.3, unlockpt.3, updwtmp.3, usleep.3, wcpcpy.3, wcpncpy.3, wcrtomb.3, wcscasecmp.3, wcscat.3, wcschr.3, wcscmp.3, wcscpy.3, wcscspn.3, wcsdup.3, wcslen.3, wcsncasecmp.3, wcsncat.3, wcsncmp.3, wcsncpy.3, wcsnlen.3, wcsnrtombs.3, wcspbrk.3, wcsrchr.3, wcsrtombs.3, wcsspn.3, wcsstr.3, wcstoimax.3, wcstok.3, wcstombs.3, wcswidth.3, wctob.3, wctomb.3, wctrans.3, wctype.3, wcwidth.3, wmemchr.3, wmemcmp.3, wmemcpy.3, wmemmove.3, wmemset.3, wordexp.3, wprintf.3, xcrypt.3, xdr.3, y0.3, cciss.4, console.4, console_codes.4, console_ioctl.4, dsp56k.4, fd.4, full.4, hd.4, hpsa.4, initrd.4, intro.4, lp.4, mem.4, mouse.4, null.4, pts.4, ram.4, random.4, rtc.4, sk98lin.4, st.4, tty.4, ttyS.4, tty_ioctl.4, vcs.4, wavelan.4, acct.5, charmap.5, dir_colors.5, filesystems.5, ftpusers.5, group.5, host.conf.5, hosts.5, hosts.equiv.5, intro.5, issue.5, locale.5, motd.5, networks.5, nologin.5, nscd.conf.5, passwd.5, proc.5, protocols.5, resolv.conf.5, rpc.5, securetty.5, services.5, shells.5, termcap.5, ttytype.5, utmp.5, armscii-8.7, arp.7, ascii.7, bootparam.7, capabilities.7, charsets.7, complex.7, cp1251.7, credentials.7, ddp.7, environ.7, epoll.7, fifo.7, futex.7, glob.7, hier.7, icmp.7, inotify.7, intro.7, ip.7, ipv6.7, iso_8859-1.7, iso_8859-10.7, iso_8859-11.7, iso_8859-13.7, iso_8859-14.7, iso_8859-15.7, iso_8859-16.7, iso_8859-2.7, iso_8859-3.7, iso_8859-4.7, iso_8859-5.7, iso_8859-6.7, iso_8859-7.7, iso_8859-8.7, iso_8859-9.7, koi8-r.7, koi8-u.7, locale.7, mailaddr.7, man.7, mq_overview.7, netdevice.7, netlink.7, numa.7, packet.7, path_resolution.7, pipe.7, posixoptions.7, pthreads.7, pty.7, raw.7, regex.7, rtld-audit.7, rtnetlink.7, sem_overview.7, shm_overview.7, sigevent.7, signal.7, socket.7, standards.7, suffixes.7, svipc.7, tcp.7, termio.7, time.7, udp.7, udplite.7, unicode.7, unix.7, uri.7, utf-8.7, x25.7, nscd.8, sync.8, tzselect.8, zdump.8, zic.8: Global fix: remove unneeded double quotes in .SH headings
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-02-24 18:01:36 +00:00
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.SH DESCRIPTION
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2004-11-03 13:51:07 +00:00
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.PP
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The
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2005-10-19 06:54:38 +00:00
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.BR futex ()
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2004-11-03 13:51:07 +00:00
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system call provides a method for
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a program to wait for a value at a given address to change, and a
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|
method to wake up anyone waiting on a particular address (while the
|
|
|
|
addresses for the same memory in separate processes may not be
|
|
|
|
equal, the kernel maps them internally so the same memory mapped in
|
|
|
|
different locations will correspond for
|
2005-10-19 06:54:38 +00:00
|
|
|
.BR futex ()
|
2007-04-12 22:42:49 +00:00
|
|
|
calls).
|
2010-08-29 04:21:27 +00:00
|
|
|
This system call is typically used to
|
2004-11-03 13:51:07 +00:00
|
|
|
implement the contended case of a lock in shared memory, as
|
|
|
|
described in
|
2006-04-21 01:24:06 +00:00
|
|
|
.BR futex (7).
|
2004-11-03 13:51:07 +00:00
|
|
|
.PP
|
2015-01-13 07:48:54 +00:00
|
|
|
When a futex operation did not finish uncontended in user space, a
|
|
|
|
.BR futex ()
|
|
|
|
call needs to be made to the kernel to arbitrate.
|
2007-04-12 22:42:49 +00:00
|
|
|
Arbitration can either mean putting the calling
|
2004-11-03 13:51:07 +00:00
|
|
|
process to sleep or, conversely, waking a waiting process.
|
|
|
|
.PP
|
2015-01-13 07:48:54 +00:00
|
|
|
Callers of
|
|
|
|
.BR futex ()
|
|
|
|
are expected to adhere to the semantics described in
|
2006-04-21 01:24:06 +00:00
|
|
|
.BR futex (7).
|
2004-11-03 13:51:07 +00:00
|
|
|
As these
|
execve.2, fallocate.2, futex.2, sched_rr_get_interval.2, select_tut.2, shmget.2, timer_getoverrun.2, times.2, pthread_attr_init.3, pthread_attr_setaffinity_np.3, pthread_cleanup_push_defer_np.3, pthread_getattr_np.3, pthread_self.3, pthread_setaffinity_np.3, pthread_tryjoin_np.3, sem_open.3, stdin.3, rtc.4, tty_ioctl.4, unix.7: Global fix: s/non-portable/nonportable/
The tendency in English, as prescribed in style guides like
Chicago MoS, is towards removing hyphens after prefixes
like "non-" etc.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2010-01-16 16:46:09 +00:00
|
|
|
semantics involve writing nonportable assembly instructions, this in turn
|
2004-11-03 13:51:07 +00:00
|
|
|
probably means that most users will in fact be library authors and not
|
|
|
|
general application developers.
|
|
|
|
.PP
|
|
|
|
The
|
|
|
|
.I uaddr
|
2015-01-13 07:48:54 +00:00
|
|
|
argument points to an integer which stores the counter (futex).
|
|
|
|
On all platforms, futexes are four-byte integers that
|
|
|
|
must be aligned on a four-byte boundary.
|
|
|
|
The operation to perform on the futex is specified in the
|
|
|
|
.I futex_op
|
|
|
|
argument;
|
|
|
|
.IR val
|
|
|
|
is a value whose meaning and purpose depends on
|
|
|
|
.IR futex_op .
|
2015-01-13 08:00:29 +00:00
|
|
|
|
|
|
|
The remaining arguments
|
|
|
|
.RI ( timeout ,
|
|
|
|
.IR uaddr2 ,
|
|
|
|
and
|
|
|
|
.IR val3 )
|
|
|
|
are required only for certain of the futex operations described below.
|
|
|
|
Where one of these arguments is not required, it is ignored.
|
|
|
|
For several blocking operations, the
|
|
|
|
.I timeout
|
|
|
|
argument is a pointer to a
|
|
|
|
.IR timespec
|
|
|
|
structure that specifies a timeout for the operation.
|
|
|
|
However, notwithstanding the prototype shown above, for some operations,
|
|
|
|
this argument is instead a four-byte integer whose meaning
|
|
|
|
is determined by the operation.
|
|
|
|
Where it is required,
|
|
|
|
.IR uaddr2
|
|
|
|
is a pointer to a second futex that is employed by the operation.
|
|
|
|
The interpretation of the final integer argument,
|
|
|
|
.IR val3 ,
|
|
|
|
depends on the operation.
|
|
|
|
|
2015-01-12 07:22:31 +00:00
|
|
|
The
|
2015-01-12 14:40:43 +00:00
|
|
|
.I futex_op
|
2015-01-12 07:22:31 +00:00
|
|
|
argument consists of two parts:
|
|
|
|
a command that specifies the operation to be performed,
|
|
|
|
bit-wise ORed with zero or or more options that
|
|
|
|
modify the behaviour of the operation.
|
2015-01-12 07:23:53 +00:00
|
|
|
The options that may be included in
|
2015-01-12 14:40:43 +00:00
|
|
|
.I futex_op
|
2015-01-12 07:23:53 +00:00
|
|
|
are as follows:
|
|
|
|
.TP
|
|
|
|
.BR FUTEX_PRIVATE_FLAG " (since Linux 2.6.22)"
|
|
|
|
.\" commit 34f01cc1f512fa783302982776895c73714ebbc2
|
|
|
|
This option bit can be employed with all futex operations.
|
|
|
|
It tells the kernel that the futex is process private and not shared
|
|
|
|
with another process.
|
|
|
|
This allows the kernel to choose the fast path for validating
|
|
|
|
the user-space address and avoids expensive VMA lookups,
|
|
|
|
taking reference counts on file backing store, and so on.
|
2015-01-13 11:25:17 +00:00
|
|
|
|
|
|
|
As a convenience,
|
|
|
|
.IR <linux/futex.h>
|
|
|
|
defines a set of constants with the suffix
|
|
|
|
.BR _PRIVATE
|
|
|
|
that are equivalents of all of the operations listed below,
|
|
|
|
.\" except the obsolete FUTEX_FD for which the "private" flag was
|
|
|
|
.\" meaningless
|
|
|
|
but with the
|
|
|
|
.BR FUTEX_PRIVATE_FLAG
|
|
|
|
ORed into the constant value.
|
|
|
|
Thus, there are
|
|
|
|
.BR FUTEX_WAIT_PRIVATE ,
|
|
|
|
.BR FUTEX_WAKE_PRIVATE ,
|
|
|
|
and so on.
|
2015-01-12 07:34:58 +00:00
|
|
|
.TP
|
|
|
|
.BR FUTEX_CLOCK_REALTIME " (since Linux 2.6.28)"
|
|
|
|
.\" commit 1acdac104668a0834cfa267de9946fac7764d486
|
2015-01-12 11:52:28 +00:00
|
|
|
This option bit can be employed only with the
|
2015-01-12 07:34:58 +00:00
|
|
|
.BR FUTEX_WAIT_BITSET
|
|
|
|
and
|
|
|
|
.BR FUTEX_WAIT_REQUEUE_PI
|
|
|
|
operations (described below).
|
|
|
|
|
|
|
|
If this option is set,
|
|
|
|
the kernel treats the user space supplied timeout as an absolute
|
|
|
|
time based on
|
|
|
|
.BR CLOCK_REALTIME .
|
|
|
|
|
|
|
|
If this option is not set,
|
2015-01-12 12:47:01 +00:00
|
|
|
the kernel treats the user space supplied timeout as relative time,
|
|
|
|
.\" FIXME I added CLOCK_MONOTONIC here. Is it correct?
|
|
|
|
measured against the
|
|
|
|
.BR CLOCK_MONOTONIC
|
|
|
|
clock.
|
2015-01-12 07:22:31 +00:00
|
|
|
.PP
|
|
|
|
The operation specified in
|
2015-01-12 14:40:43 +00:00
|
|
|
.I futex_op
|
2015-01-12 07:22:31 +00:00
|
|
|
is one of the following:
|
2004-11-03 13:51:07 +00:00
|
|
|
.TP
|
2015-01-12 12:24:43 +00:00
|
|
|
.BR FUTEX_WAIT " (since Linux 2.6.0)"
|
|
|
|
.\" Strictly speaking, since some time in 2.5.x
|
2015-01-12 13:01:22 +00:00
|
|
|
This operation tests that the value at the
|
|
|
|
location pointed to by the futex address
|
2004-11-03 13:51:07 +00:00
|
|
|
.I uaddr
|
|
|
|
still contains the value
|
|
|
|
.IR val ,
|
2015-01-12 13:01:22 +00:00
|
|
|
and then sleeps awaiting
|
2007-06-22 17:16:20 +00:00
|
|
|
.B FUTEX_WAKE
|
2015-01-12 13:01:22 +00:00
|
|
|
on the futex address.
|
|
|
|
The test and sleep steps are performed atomically.
|
|
|
|
If the futex value does not match
|
|
|
|
.IR val ,
|
2015-01-13 08:11:03 +00:00
|
|
|
then the call fails immediately with the error
|
2015-01-12 13:01:22 +00:00
|
|
|
.BR EWOULDBLOCK .
|
|
|
|
.\" FIXME I added the following sentence. Please confirm that it is correct.
|
|
|
|
The purpose of the test step is to detect races where
|
|
|
|
another process changes that value of the futex between
|
|
|
|
the time it was last checked and the time of the
|
|
|
|
.BR FUTEX_WAIT
|
2015-01-13 15:29:59 +00:00
|
|
|
operation.
|
2015-01-12 12:41:46 +00:00
|
|
|
|
2007-04-12 22:42:49 +00:00
|
|
|
If the
|
2004-11-03 13:51:07 +00:00
|
|
|
.I timeout
|
2015-01-12 12:47:01 +00:00
|
|
|
argument is non-NULL, its contents specify a relative timeout for the wait
|
|
|
|
.\" FIXME I added CLOCK_MONOTONIC here. Is it correct?
|
|
|
|
measured according to the
|
|
|
|
.BR CLOCK_MONOTONIC
|
|
|
|
clock.
|
2013-09-04 08:24:01 +00:00
|
|
|
(This interval will be rounded up to the system clock granularity,
|
|
|
|
and kernel scheduling delays mean that the
|
|
|
|
blocking interval may overrun by a small amount.)
|
|
|
|
If
|
|
|
|
.I timeout
|
|
|
|
is NULL, the call blocks indefinitely.
|
2014-06-04 07:48:23 +00:00
|
|
|
|
2007-04-12 22:42:49 +00:00
|
|
|
The arguments
|
2004-11-03 13:51:07 +00:00
|
|
|
.I uaddr2
|
|
|
|
and
|
|
|
|
.I val3
|
|
|
|
are ignored.
|
|
|
|
|
|
|
|
For
|
2006-04-21 01:24:06 +00:00
|
|
|
.BR futex (7),
|
2004-11-03 13:51:07 +00:00
|
|
|
this call is executed if decrementing the count gave a negative value
|
|
|
|
(indicating contention), and will sleep until another process releases
|
2007-06-22 17:16:20 +00:00
|
|
|
the futex and executes the
|
|
|
|
.B FUTEX_WAKE
|
|
|
|
operation.
|
2004-11-03 13:51:07 +00:00
|
|
|
.TP
|
2015-01-12 12:24:43 +00:00
|
|
|
.BR FUTEX_WAKE " (since Linux 2.6.0)"
|
|
|
|
.\" Strictly speaking, since Linux 2.5.x
|
2015-01-12 13:01:22 +00:00
|
|
|
This operation wakes at most
|
|
|
|
.I val
|
|
|
|
processes waiting (i.e., inside
|
|
|
|
.BR FUTEX_WAIT )
|
|
|
|
on the futex at the address
|
|
|
|
.IR uaddr .
|
|
|
|
Most commonly,
|
|
|
|
.I val
|
|
|
|
is specified as either 1 (wake up a single waiter) or
|
|
|
|
.BR INT_MAX
|
|
|
|
(wake up all waiters).
|
2015-01-13 08:25:04 +00:00
|
|
|
.\" FIXME Please confirm that the following is correct:
|
|
|
|
No guarantee is provided about which waiters are awoken
|
|
|
|
(e.g., a waiter with a higher scheduling priority is not guaranteed
|
|
|
|
to be awoken in preference to a waiter with a lower priority).
|
2014-06-04 07:48:23 +00:00
|
|
|
|
2004-11-03 13:51:07 +00:00
|
|
|
The arguments
|
|
|
|
.IR timeout ,
|
|
|
|
.I uaddr2
|
|
|
|
and
|
|
|
|
.I val3
|
|
|
|
are ignored.
|
|
|
|
|
|
|
|
For
|
2006-04-21 01:24:06 +00:00
|
|
|
.BR futex (7),
|
2004-11-03 13:51:07 +00:00
|
|
|
this is executed if incrementing
|
|
|
|
the count showed that there were waiters, once the futex value has been set
|
|
|
|
to 1 (indicating that it is available).
|
2015-01-13 15:47:22 +00:00
|
|
|
.TP
|
|
|
|
.BR FUTEX_FD " (from Linux 2.6.0 up to and including Linux 2.6.25)"
|
|
|
|
.\" Strictly speaking, from Linux 2.5.x to 2.6.25
|
|
|
|
This operation creates a file descriptor that is associated with the futex at
|
|
|
|
.IR uaddr .
|
|
|
|
.\" , suitable for .BR poll (2).
|
|
|
|
The calling process must close the returned file descriptor after use.
|
|
|
|
When another process performs a
|
|
|
|
.BR FUTEX_WAKE
|
|
|
|
on the futex, the file descriptor indicates as being readable with
|
|
|
|
.BR select (2),
|
|
|
|
.BR poll (2),
|
|
|
|
and
|
|
|
|
.BR epoll (7)
|
|
|
|
|
|
|
|
The file descriptor can be used to obtain asynchronous notifications:
|
|
|
|
if
|
|
|
|
.I val
|
|
|
|
is nonzero, then when another process executes a
|
|
|
|
.BR FUTEX_WAKE ,
|
|
|
|
the caller will receive the signal number that was passed in
|
|
|
|
.IR val .
|
|
|
|
|
|
|
|
The arguments
|
|
|
|
.IR timeout ,
|
|
|
|
.I uaddr2
|
|
|
|
and
|
|
|
|
.I val3
|
|
|
|
are ignored.
|
|
|
|
|
|
|
|
To prevent race conditions, the caller should test if the futex has
|
|
|
|
been upped after
|
|
|
|
.B FUTEX_FD
|
|
|
|
returns.
|
|
|
|
|
|
|
|
Because it was inherently racy,
|
|
|
|
.B FUTEX_FD
|
|
|
|
has been removed
|
|
|
|
.\" commit 82af7aca56c67061420d618cc5a30f0fd4106b80
|
|
|
|
from Linux 2.6.26 onward.
|
|
|
|
.TP
|
|
|
|
.BR FUTEX_REQUEUE " (since Linux 2.6.0)"
|
|
|
|
.\" Strictly speaking: from Linux 2.5.70
|
|
|
|
.\"
|
|
|
|
.\" FIXME I added this warning. Okay?
|
|
|
|
.IR "Avoid using this operation" .
|
|
|
|
It is broken (unavoidably racy) for its intended purpose.
|
|
|
|
Use
|
|
|
|
.BR FUTEX_CMP_REQUEUE
|
|
|
|
instead.
|
|
|
|
|
|
|
|
This operation performs the same task as
|
|
|
|
.BR FUTEX_CMP_REQUEUE ,
|
|
|
|
except that no check is made using the value in
|
|
|
|
.IR val3 .
|
|
|
|
(The argument
|
|
|
|
.I val3
|
|
|
|
is ignored.)
|
|
|
|
.TP
|
|
|
|
.BR FUTEX_CMP_REQUEUE " (since Linux 2.6.7)"
|
|
|
|
This operation was added as a replacement for the earlier
|
|
|
|
.BR FUTEX_REQUEUE ,
|
|
|
|
because that operation was racy for its intended use.
|
|
|
|
|
|
|
|
As with
|
|
|
|
.BR FUTEX_REQUEUE ,
|
|
|
|
the
|
|
|
|
.BR FUTEX_CMP_REQUEUE
|
|
|
|
operation is used to avoid a "thundering herd" effect when
|
|
|
|
.B FUTEX_WAKE
|
|
|
|
is used and all processes woken up need to acquire another futex.
|
|
|
|
It differs from
|
|
|
|
.BR FUTEX_REQUEUE
|
|
|
|
in that it first checks whether the location
|
|
|
|
.I uaddr
|
|
|
|
still contains the value
|
|
|
|
.IR val3 .
|
|
|
|
If not, the operation fails with the error
|
|
|
|
.BR EAGAIN .
|
|
|
|
.\" FIXME I added the following sentence on rational for FUTEX_CMP_REQUEUE.
|
|
|
|
.\" Is it correct? SHould it be expanded?
|
|
|
|
This additional feature of
|
|
|
|
.BR FUTEX_CMP_REQUEUE
|
|
|
|
can be used by the caller to (atomically) detect changes
|
|
|
|
in the value of the target futex at
|
|
|
|
.IR uaddr2 .
|
|
|
|
|
|
|
|
The operation wakes up a maximum of
|
|
|
|
.I val
|
|
|
|
waiters that are waiting on the futex at
|
|
|
|
.IR uaddr .
|
|
|
|
If there are more than
|
|
|
|
.I val
|
|
|
|
waiters, then the remaining waiters are removed
|
|
|
|
from the wait queue of the source futex at
|
|
|
|
.I uaddr
|
|
|
|
and added to the wait queue of the target futex at
|
|
|
|
.IR uaddr2 .
|
|
|
|
The
|
|
|
|
.I timeout
|
|
|
|
argument is (ab)used to specify a cap on the number of waiters
|
|
|
|
that are requeued to the futex at
|
|
|
|
.IR uaddr2 ;
|
|
|
|
the kernel casts the
|
|
|
|
.I timeout
|
|
|
|
value to
|
|
|
|
.IR u32 .
|
|
|
|
|
|
|
|
.\" FIXME Please review the following new paragraph to see if it is
|
|
|
|
.\" accurate.
|
|
|
|
Typical values to specify for
|
|
|
|
.I val
|
|
|
|
are 0 or or 1.
|
|
|
|
(Specifying
|
|
|
|
.BR INT_MAX
|
|
|
|
is not useful, because it would make the
|
|
|
|
.BR FUTEX_CMP_REQUEUE
|
|
|
|
operation equivalent to
|
|
|
|
.BR FUTEX_WAKE .)
|
|
|
|
The cap value specified via the (abused)
|
|
|
|
.I timeout
|
|
|
|
argument is typically either 1 or
|
|
|
|
.BR INT_MAX .
|
|
|
|
(Specifying the argument as 0 is not useful, because it would make the
|
|
|
|
.BR FUTEX_CMP_REQUEUE
|
|
|
|
operation equivalent to
|
|
|
|
.BR FUTEX_WAIT .)
|
2015-01-12 14:38:13 +00:00
|
|
|
.\"
|
|
|
|
.\" FIXME I added some FUTEX_WAKE_OP text, and I'd be happy if someone
|
|
|
|
.\" checked it.
|
2004-11-03 13:51:07 +00:00
|
|
|
.TP
|
2015-01-12 09:27:13 +00:00
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.BR FUTEX_WAKE_OP " (since Linux 2.6.14)"
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.\" commit 4732efbeb997189d9f9b04708dc26bf8613ed721
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2015-01-12 14:38:13 +00:00
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.\" Author: Jakub Jelinek <jakub@redhat.com>
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.\" Date: Tue Sep 6 15:16:25 2005 -0700
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This operation was added to support some user-space use cases
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where more than one futex must be handled at the same time.
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The most notable example is the implementation of
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.BR pthread_cond_signal (3),
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which requires operations on two futexes,
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the one used to implement the mutex and the one used in the implementation
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of the wait queue associated with the condition variable.
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.BR FUTEX_WAKE_OP
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allows such cases to be implemented without leading to
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high rates of contention and context switching.
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The
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.BR FUTEX_WAIT_OP
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operation is equivalent to atomically executing the following code:
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.in +4n
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.nf
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int oldval = *(int *) uaddr2;
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*(int *) uaddr2 = oldval \fIop\fP \fIoparg\fP;
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futex(uaddr, FUTEX_WAKE, val, 0, 0, 0);
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if (oldval \fIcmp\fP \fIcmparg\fP)
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futex(uaddr2, FUTEX_WAKE, nr_wake2, 0, 0, 0);
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.fi
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.in
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In other words,
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.BR FUTEX_WAIT_OP
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does the following:
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.RS
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.IP * 3
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saves the original value of the futex at
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.IR uaddr2 ;
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.IP *
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performs an operation to modify the value of the futex at
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.IR uaddr2 ;
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.IP *
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wakes up a maximum of
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.I val
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waiters on the futex
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.IR uaddr ;
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and
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.IP *
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dependent on the results of a test of the original value of the futex at
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.IR uaddr2 ,
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wakes up a maximum of
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.I nr_wake2
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waiters on the futex
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.IR uaddr2 .
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.RE
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.IP
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The
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.I nr_wake2
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value is actually the
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.BR futex ()
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.I timeout
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argument (ab)used to specify how many of the waiters on the futex at
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.IR uaddr2
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are to be woken up;
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the kernel casts the
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.I timeout
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value to
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.IR u32 .
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The operation and comparison that are to be performed are encoded
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in the bits of the argument
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.IR val3 .
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Pictorially, the encoding is:
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.in +4n
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.nf
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+-----+-----+---------------+---------------+
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| op | cmp | oparg | cmparg |
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+-----+-----+---------------+---------------+
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# of bits: 4 4 12 12
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.fi
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.in
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Expressed in code, the encoding is:
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.in +4n
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.nf
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#define FUTEX_OP(op, oparg, cmp, cmparg) \\
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(((op & 0xf) << 28) | \\
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((cmp & 0xf) << 24) | \\
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((oparg & 0xfff) << 12) | \\
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(cmparg & 0xfff))
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.fi
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.in
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In the above,
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.I op
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and
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.I cmp
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are each one of the codes listed below.
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The
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.I oparg
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and
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.I cmparg
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components are literal numeric values, except as noted below.
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The
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.I op
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component has one of the following values:
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.in +4n
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.nf
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FUTEX_OP_SET 0 /* uaddr2 = oparg; */
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FUTEX_OP_ADD 1 /* uaddr2 += oparg; */
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FUTEX_OP_OR 2 /* uaddr2 |= oparg; */
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FUTEX_OP_ANDN 3 /* uaddr2 &= ~oparg; */
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FUTEX_OP_XOR 4 /* uaddr2 ^= oparg; */
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.fi
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.in
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In addition, bit-wise ORing the following value into
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.I op
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causes
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.IR "(1\ <<\ oparg)"
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to be used as the operand:
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.in +4n
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.nf
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FUTEX_OP_ARG_SHIFT 8 /* Use (1 << oparg) as operand */
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.fi
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.in
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The
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.I cmp
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field is one of the following:
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.in +4n
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.nf
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FUTEX_OP_CMP_EQ 0 /* if (oldval == cmparg) wake */
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FUTEX_OP_CMP_NE 1 /* if (oldval != cmparg) wake */
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FUTEX_OP_CMP_LT 2 /* if (oldval < cmparg) wake */
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FUTEX_OP_CMP_LE 3 /* if (oldval <= cmparg) wake */
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FUTEX_OP_CMP_GT 4 /* if (oldval > cmparg) wake */
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FUTEX_OP_CMP_GE 5 /* if (oldval >= cmparg) wake */
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.fi
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.in
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The return value of
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.BR FUTEX_WAKE_OP
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is the sum of the number of waiters woken on the futex
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.IR uaddr
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plus the number of waiters woken on the futex
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.IR uaddr2 .
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2015-01-12 09:27:13 +00:00
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.TP
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2015-01-13 14:34:17 +00:00
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.BR FUTEX_WAIT_BITSET " (since Linux 2.6.25)"
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.\" commit cd689985cf49f6ff5c8eddc48d98b9d581d9475d
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2015-01-13 15:05:32 +00:00
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This operation is like
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2015-01-13 14:34:17 +00:00
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.BR FUTEX_WAIT
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except that
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.I val3
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is used to provide a 32-bit bitset to the kernel.
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This bitset is stored in the kernel-internal state of the waiter.
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See the description of
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.BR FUTEX_WAKE_BITSET
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for further details.
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2015-01-13 15:05:32 +00:00
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The
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.BR FUTEX_WAIT_BITSET
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also interprets the
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.I timeout
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argument differently from
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.BR FUTEX_WAIT .
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See the discussion of
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.BR FUTEX_CLOCK_REALTIME ,
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above.
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2015-01-13 14:34:17 +00:00
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The
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.I uaddr2
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argument is ignored.
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.TP
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2015-01-12 09:27:13 +00:00
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.BR FUTEX_WAKE_BITSET " (since Linux 2.6.25)"
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.\" commit cd689985cf49f6ff5c8eddc48d98b9d581d9475d
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2015-01-13 14:36:37 +00:00
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This operation is the same as
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.BR FUTEX_WAKE
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except that the
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.I val3
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argument is used to provide a 32-bit bitset to the kernel.
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2015-01-13 14:48:51 +00:00
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This bitset is used to select which waiters should be woken up.
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The selection is done by a bit-wise AND of the "wake" bitset
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(i.e., the value in
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.IR val3 )
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and the bitset which is stored in the kernel-internal
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2015-01-13 15:51:29 +00:00
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state of the waiter (the "wait" bitset that is set using
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2015-01-13 14:48:51 +00:00
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.BR FUTEX_WAIT_BITSET ).
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All of the waiters for which the result of the AND is nonzero are woken up;
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the remaining waiters are left sleeping.
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2015-01-13 15:29:01 +00:00
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.\" FIXME please review this paragraph that I added
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The effect of
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.BR FUTEX_WAIT_BITSET
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and
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.BR FUTEX_WAKE_BITSET
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is to allow selective wake-ups among multiple waiters that are waiting
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on the same futex;
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since a futex has a size of 32 bits,
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these operations provide 32 wakeup "channels".
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(The
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.BR FUTEX_WAIT
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and
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.BR FUTEX_WAKE
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operations correspond to
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.BR FUTEX_WAIT_BITSET
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and
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.BR FUTEX_WAKE_BITSET
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operations where the bitsets are all ones.)
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2015-01-13 15:51:29 +00:00
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Note, however, that using this bitset multiplexing feature on a
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2015-01-13 15:29:01 +00:00
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futex is less efficient than simply using multiple futexes,
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because employing bitset multiplexing requires the kernel
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to check all waiters on a futex,
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including those that are not interested in being woken up
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(i.e., they do not have the relevant bit set in their "wait" bitset).
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.\" According to http://locklessinc.com/articles/futex_cheat_sheet/:
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.\"
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.\" "The original reason for the addition of these extensions
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.\" was to improve the performance of pthread read-write locks
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.\" in glibc. However, the pthreads library no longer uses the
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.\" same locking algorithm, and these extensions are not used
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.\" without the bitset parameter being all ones.
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.\"
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.\" The page goes on to note that the FUTEX_WAIT_BITSET operation
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.\" is nevertheless used (with a bitset of all ones) in order to
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.\" obtain the absolute timeout functionality that is useful
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.\" for efficiently implementing Pthreads APIs (which use absolute
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.\" timeouts); FUTEX_WAIT provides only relative timeouts.
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2015-01-13 14:48:51 +00:00
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The
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.I uaddr2
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and
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.I timeout
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arguments are ignored.
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2015-01-12 09:27:13 +00:00
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.TP
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.BR FUTEX_LOCK_PI " (since Linux 2.6.18)"
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.\" commit c87e2837be82df479a6bae9f155c43516d2feebc
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.\" FIXME to complete
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2015-01-13 14:11:03 +00:00
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.\"
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2015-01-13 16:16:55 +00:00
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.\" FIXME Employs 'timeout' argument, with absolute time value on
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.\" CLOCK_REALTIME clock; 'timeout' can be NULL
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2015-01-13 14:11:03 +00:00
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.\"
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2015-01-12 09:27:13 +00:00
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[As yet undocumented]
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.TP
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.BR FUTEX_UNLOCK_PI " (since Linux 2.6.18)"
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.\" commit c87e2837be82df479a6bae9f155c43516d2feebc
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.\" FIXME to complete
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[As yet undocumented]
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.TP
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.BR FUTEX_TRYLOCK_PI " (since Linux 2.6.18)"
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.\" commit c87e2837be82df479a6bae9f155c43516d2feebc
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.\" FIXME to complete
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[As yet undocumented]
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.TP
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.BR FUTEX_CMP_REQUEUE_PI " (since Linux 2.6.31)"
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.\" commit 52400ba946759af28442dee6265c5c0180ac7122
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.\" FIXME to complete
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[As yet undocumented]
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.TP
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.BR FUTEX_WAIT_REQUEUE_PI " (since Linux 2.6.31)"
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.\" commit 52400ba946759af28442dee6265c5c0180ac7122
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.\" FIXME to complete
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2015-01-13 16:16:55 +00:00
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.\"
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.\" FIXME Employs 'timeout' argument, supports FUTEX_CLOCK_REALTIME
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.\" 'timeout' can be NULL
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.\"
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2015-01-12 09:27:13 +00:00
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[As yet undocumented]
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getent.1, intro.1, time.1, _exit.2, _syscall.2, accept.2, access.2, acct.2, adjtimex.2, alarm.2, alloc_hugepages.2, arch_prctl.2, bdflush.2, bind.2, brk.2, cacheflush.2, capget.2, chdir.2, chmod.2, chown.2, chroot.2, clock_getres.2, clock_nanosleep.2, clone.2, close.2, connect.2, create_module.2, delete_module.2, dup.2, epoll_create.2, epoll_ctl.2, epoll_wait.2, eventfd.2, execve.2, exit_group.2, faccessat.2, fchmodat.2, fchownat.2, fcntl.2, flock.2, fork.2, fstatat.2, fsync.2, futex.2, futimesat.2, get_kernel_syms.2, get_robust_list.2, get_thread_area.2, getcpu.2, getdents.2, getdomainname.2, getgid.2, getgroups.2, gethostname.2, getitimer.2, getpagesize.2, getpeername.2, getpid.2, getpriority.2, getresuid.2, getrlimit.2, getrusage.2, getsid.2, getsockname.2, getsockopt.2, gettid.2, gettimeofday.2, getuid.2, getunwind.2, getxattr.2, idle.2, init_module.2, inotify_add_watch.2, inotify_init.2, inotify_rm_watch.2, intro.2, io_cancel.2, io_destroy.2, io_getevents.2, io_setup.2, io_submit.2, ioctl.2, ioctl_list.2, ioperm.2, iopl.2, ioprio_set.2, ipc.2, kcmp.2, kill.2, killpg.2, link.2, linkat.2, listen.2, listxattr.2, llseek.2, lookup_dcookie.2, lseek.2, madvise.2, migrate_pages.2, mincore.2, mkdir.2, mkdirat.2, mknod.2, mknodat.2, mlock.2, mmap.2, mmap2.2, modify_ldt.2, mount.2, move_pages.2, mprotect.2, mq_getsetattr.2, mremap.2, msgctl.2, msgget.2, msgop.2, msync.2, nanosleep.2, nfsservctl.2, nice.2, open.2, openat.2, outb.2, pause.2, pciconfig_read.2, perf_event_open.2, perfmonctl.2, personality.2, pipe.2, pivot_root.2, poll.2, posix_fadvise.2, prctl.2, pread.2, process_vm_readv.2, ptrace.2, query_module.2, quotactl.2, read.2, readahead.2, readdir.2, readlink.2, readlinkat.2, readv.2, reboot.2, recv.2, remap_file_pages.2, removexattr.2, rename.2, renameat.2, rmdir.2, rt_sigqueueinfo.2, sched_get_priority_max.2, sched_rr_get_interval.2, sched_setaffinity.2, sched_setparam.2, sched_setscheduler.2, sched_yield.2, select.2, semctl.2, semget.2, semop.2, send.2, sendfile.2, set_thread_area.2, set_tid_address.2, seteuid.2, setfsgid.2, setfsuid.2, setgid.2, setpgid.2, setresuid.2, setreuid.2, setsid.2, setuid.2, setup.2, setxattr.2, shmctl.2, shmget.2, shmop.2, shutdown.2, sigaction.2, sigaltstack.2, signal.2, signalfd.2, sigpending.2, sigprocmask.2, sigreturn.2, sigsuspend.2, sigwaitinfo.2, socket.2, socketcall.2, socketpair.2, splice.2, stat.2, statfs.2, stime.2, swapon.2, symlink.2, symlinkat.2, sync.2, sync_file_range.2, sysctl.2, sysfs.2, sysinfo.2, syslog.2, tee.2, time.2, timerfd_create.2, times.2, tkill.2, truncate.2, umask.2, umount.2, uname.2, unimplemented.2, unlink.2, unlinkat.2, uselib.2, ustat.2, utime.2, utimensat.2, vfork.2, vhangup.2, vm86.2, vmsplice.2, wait.2, wait4.2, write.2, CPU_SET.3, INFINITY.3, MB_CUR_MAX.3, MB_LEN_MAX.3, __setfpucw.3, a64l.3, abort.3, abs.3, acos.3, acosh.3, addseverity.3, adjtime.3, aio_cancel.3, aio_error.3, aio_fsync.3, aio_read.3, aio_return.3, aio_suspend.3, aio_write.3, alloca.3, argz_add.3, asin.3, asinh.3, asprintf.3, assert.3, assert_perror.3, atan.3, atan2.3, atanh.3, atexit.3, atof.3, atoi.3, backtrace.3, basename.3, bcmp.3, bcopy.3, bindresvport.3, bsd_signal.3, bsearch.3, bstring.3, btowc.3, btree.3, byteorder.3, bzero.3, cabs.3, cacos.3, cacosh.3, canonicalize_file_name.3, carg.3, casin.3, casinh.3, catan.3, catanh.3, catgets.3, catopen.3, cbrt.3, ccos.3, ccosh.3, ceil.3, cerf.3, cexp.3, cexp2.3, cfree.3, cimag.3, clearenv.3, clock.3, clock_getcpuclockid.3, clog.3, clog10.3, clog2.3, closedir.3, cmsg.3, confstr.3, conj.3, copysign.3, cos.3, cosh.3, cpow.3, cproj.3, creal.3, crypt.3, csin.3, csinh.3, csqrt.3, ctan.3, ctanh.3, ctermid.3, ctime.3, daemon.3, dbopen.3, des_crypt.3, difftime.3, dirfd.3, div.3, dl_iterate_phdr.3, dlopen.3, dprintf.3, drand48.3, drand48_r.3, dysize.3, ecvt.3, ecvt_r.3, encrypt.3, end.3, endian.3, envz_add.3, erf.3, erfc.3, err.3, errno.3, error.3, ether_aton.3, euidaccess.3, exec.3, exit.3, exp.3, exp10.3, exp2.3, expm1.3, fabs.3, fclose.3, fcloseall.3, fdim.3, fenv.3, ferror.3, fexecve.3, fflush.3, ffs.3, fgetgrent.3, fgetpwent.3, fgetwc.3, fgetws.3, finite.3, flockfile.3, floor.3, fma.3, fmax.3, fmemopen.3, fmin.3, fmod.3, fmtmsg.3, fnmatch.3, fopen.3, fpathconf.3, fpclassify.3, fpurge.3, fputwc.3, fputws.3, fread.3, frexp.3, fseek.3, fseeko.3, ftime.3, ftok.3, fts.3, ftw.3, futimes.3, fwide.3, gamma.3, gcvt.3, getaddrinfo.3, getaddrinfo_a.3, getauxval.3, getcontext.3, getcwd.3, getdate.3, getdirentries.3, getdtablesize.3, getenv.3, getfsent.3, getgrent.3, getgrent_r.3, getgrnam.3, getgrouplist.3, gethostbyname.3, gethostid.3, getipnodebyname.3, getline.3, getloadavg.3, getlogin.3, getmntent.3, getnameinfo.3, getnetent.3, getnetent_r.3, getopt.3, getpass.3, getprotoent.3, getprotoent_r.3, getpt.3, getpw.3, getpwent.3, getpwent_r.3, getpwnam.3, getrpcent.3, getrpcent_r.3, getrpcport.3, gets.3, getservent.3, getservent_r.3, getspnam.3, getttyent.3, getumask.3, getusershell.3, getutent.3, getw.3, getwchar.3, glob.3, grantpt.3, gsignal.3, hash.3, hsearch.3, hypot.3, iconv.3, iconv_close.3, iconv_open.3, ilogb.3, index.3, inet.3, inet_ntop.3, inet_pton.3, infnan.3, initgroups.3, insque.3, intro.3, isalpha.3, isatty.3, isgreater.3, iswalnum.3, iswalpha.3, iswblank.3, iswcntrl.3, iswctype.3, iswdigit.3, iswgraph.3, iswlower.3, iswprint.3, iswpunct.3, iswspace.3, iswupper.3, iswxdigit.3, j0.3, key_setsecret.3, ldexp.3, lgamma.3, lio_listio.3, localeconv.3, lockf.3, log.3, log10.3, log1p.3, log2.3, logb.3, login.3, longjmp.3, lrint.3, lround.3, lsearch.3, lseek64.3, makecontext.3, makedev.3, malloc.3, malloc_hook.3, mblen.3, mbrlen.3, mbrtowc.3, mbsinit.3, mbsnrtowcs.3, mbsrtowcs.3, mbstowcs.3, mbtowc.3, memccpy.3, memchr.3, memcmp.3, memcpy.3, memfrob.3, memmem.3, memmove.3, mempcpy.3, memset.3, mkdtemp.3, mkfifo.3, mkfifoat.3, mkstemp.3, mktemp.3, modf.3, mpool.3, mq_close.3, mq_getattr.3, mq_notify.3, mq_open.3, mq_receive.3, mq_send.3, mq_unlink.3, mtrace.3, nan.3, netlink.3, nextafter.3, nl_langinfo.3, offsetof.3, on_exit.3, opendir.3, openpty.3, perror.3, popen.3, posix_fallocate.3, posix_memalign.3, posix_openpt.3, pow.3, pow10.3, printf.3, profil.3, program_invocation_name.3, psignal.3, pthread_kill_other_threads_np.3, ptsname.3, putenv.3, putgrent.3, putpwent.3, puts.3, putwchar.3, qecvt.3, qsort.3, queue.3, raise.3, rand.3, random.3, random_r.3, rcmd.3, re_comp.3, readdir.3, realpath.3, recno.3, regex.3, remainder.3, remove.3, remquo.3, resolver.3, rewinddir.3, rexec.3, rint.3, round.3, rpc.3, rpmatch.3, rtime.3, rtnetlink.3, scalb.3, scalbln.3, scandir.3, scandirat.3, scanf.3, seekdir.3, sem_close.3, sem_destroy.3, sem_getvalue.3, sem_init.3, sem_open.3, sem_post.3, sem_unlink.3, sem_wait.3, setaliasent.3, setbuf.3, setenv.3, setjmp.3, setlocale.3, setlogmask.3, setnetgrent.3, shm_open.3, siginterrupt.3, signbit.3, significand.3, sigpause.3, sigqueue.3, sigset.3, sigsetops.3, sigvec.3, sin.3, sincos.3, sinh.3, sleep.3, sockatmark.3, sqrt.3, statvfs.3, stdarg.3, stdin.3, stdio.3, stdio_ext.3, stpcpy.3, stpncpy.3, strcasecmp.3, strcat.3, strchr.3, strcmp.3, strcoll.3, strcpy.3, strdup.3, strerror.3, strfmon.3, strfry.3, strftime.3, string.3, strlen.3, strnlen.3, strpbrk.3, strptime.3, strsep.3, strsignal.3, strspn.3, strstr.3, strtod.3, strtoimax.3, strtok.3, strtol.3, strtoul.3, strverscmp.3, strxfrm.3, swab.3, sysconf.3, syslog.3, system.3, sysv_signal.3, tan.3, tanh.3, tcgetpgrp.3, tcgetsid.3, telldir.3, tempnam.3, termios.3, tgamma.3, timegm.3, timeradd.3, tmpfile.3, tmpnam.3, toascii.3, toupper.3, towctrans.3, towlower.3, towupper.3, trunc.3, tsearch.3, ttyname.3, ttyslot.3, tzset.3, ualarm.3, ulimit.3, ungetwc.3, unlocked_stdio.3, unlockpt.3, updwtmp.3, usleep.3, wcpcpy.3, wcpncpy.3, wcrtomb.3, wcscasecmp.3, wcscat.3, wcschr.3, wcscmp.3, wcscpy.3, wcscspn.3, wcsdup.3, wcslen.3, wcsncasecmp.3, wcsncat.3, wcsncmp.3, wcsncpy.3, wcsnlen.3, wcsnrtombs.3, wcspbrk.3, wcsrchr.3, wcsrtombs.3, wcsspn.3, wcsstr.3, wcstoimax.3, wcstok.3, wcstombs.3, wcswidth.3, wctob.3, wctomb.3, wctrans.3, wctype.3, wcwidth.3, wmemchr.3, wmemcmp.3, wmemcpy.3, wmemmove.3, wmemset.3, wordexp.3, wprintf.3, xcrypt.3, xdr.3, y0.3, cciss.4, console.4, console_codes.4, console_ioctl.4, dsp56k.4, fd.4, full.4, hd.4, hpsa.4, initrd.4, intro.4, lp.4, mem.4, mouse.4, null.4, pts.4, ram.4, random.4, rtc.4, sk98lin.4, st.4, tty.4, ttyS.4, tty_ioctl.4, vcs.4, wavelan.4, acct.5, charmap.5, dir_colors.5, filesystems.5, ftpusers.5, group.5, host.conf.5, hosts.5, hosts.equiv.5, intro.5, issue.5, locale.5, motd.5, networks.5, nologin.5, nscd.conf.5, passwd.5, proc.5, protocols.5, resolv.conf.5, rpc.5, securetty.5, services.5, shells.5, termcap.5, ttytype.5, utmp.5, armscii-8.7, arp.7, ascii.7, bootparam.7, capabilities.7, charsets.7, complex.7, cp1251.7, credentials.7, ddp.7, environ.7, epoll.7, fifo.7, futex.7, glob.7, hier.7, icmp.7, inotify.7, intro.7, ip.7, ipv6.7, iso_8859-1.7, iso_8859-10.7, iso_8859-11.7, iso_8859-13.7, iso_8859-14.7, iso_8859-15.7, iso_8859-16.7, iso_8859-2.7, iso_8859-3.7, iso_8859-4.7, iso_8859-5.7, iso_8859-6.7, iso_8859-7.7, iso_8859-8.7, iso_8859-9.7, koi8-r.7, koi8-u.7, locale.7, mailaddr.7, man.7, mq_overview.7, netdevice.7, netlink.7, numa.7, packet.7, path_resolution.7, pipe.7, posixoptions.7, pthreads.7, pty.7, raw.7, regex.7, rtld-audit.7, rtnetlink.7, sem_overview.7, shm_overview.7, sigevent.7, signal.7, socket.7, standards.7, suffixes.7, svipc.7, tcp.7, termio.7, time.7, udp.7, udplite.7, unicode.7, unix.7, uri.7, utf-8.7, x25.7, nscd.8, sync.8, tzselect.8, zdump.8, zic.8: Global fix: remove unneeded double quotes in .SH headings
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-02-24 18:01:36 +00:00
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.SH RETURN VALUE
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2004-11-03 13:51:07 +00:00
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.PP
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2012-08-13 12:50:26 +00:00
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In the event of an error, all operations return \-1, and set
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.I errno
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to indicate the error.
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The return value on success depends on the operation,
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as described in the following list:
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2004-11-03 13:51:07 +00:00
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.TP
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.B FUTEX_WAIT
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2007-06-22 17:16:20 +00:00
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Returns 0 if the process was woken by a
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.B FUTEX_WAKE
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call.
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2012-08-13 12:50:26 +00:00
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See ERRORS for the various possible error returns.
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2004-11-03 13:51:07 +00:00
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.TP
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.B FUTEX_WAKE
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Returns the number of processes woken up.
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.TP
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.B FUTEX_FD
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Returns the new file descriptor associated with the futex.
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.TP
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.B FUTEX_REQUEUE
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Returns the number of processes woken up.
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.TP
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.B FUTEX_CMP_REQUEUE
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2015-01-13 05:40:25 +00:00
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Returns the total number of processes woken up or requeued to the futex at
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.IR uaddr2 .
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If this value is greater than
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.IR val ,
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then difference is the number of waiters requeued to the futex at
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.IR uaddr2 .
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2015-01-12 13:14:21 +00:00
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.\"
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.\" FIXME Add success returns for other operations
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2004-11-03 13:51:07 +00:00
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.SH ERRORS
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.TP
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.B EACCES
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No read access to futex memory.
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.TP
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.B EAGAIN
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2007-06-22 17:16:20 +00:00
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.B FUTEX_CMP_REQUEUE
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2012-08-13 12:50:26 +00:00
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detected that the value pointed to by
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2012-08-13 12:25:13 +00:00
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.I uaddr
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is not equal to the expected value
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.IR val3 .
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2014-06-04 08:32:19 +00:00
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.\" FIXME: Is the following sentence correct?
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2004-11-03 13:51:07 +00:00
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(This probably indicates a race;
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2007-06-22 17:16:20 +00:00
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use the safe
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.B FUTEX_WAKE
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now.)
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2004-11-03 13:51:07 +00:00
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.TP
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.B EFAULT
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2014-06-04 06:54:43 +00:00
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A required pointer argument (i.e.,
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.IR uaddr ,
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.IR uaddr2 ,
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or
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.IR timeout )
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2014-06-04 07:39:08 +00:00
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did not point to a valid user-space address.
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2004-11-03 13:51:07 +00:00
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.TP
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2012-08-13 12:25:13 +00:00
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.B EINTR
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2012-08-13 12:50:26 +00:00
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A
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2012-08-13 12:25:13 +00:00
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.B FUTEX_WAIT
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2015-01-13 08:19:07 +00:00
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or
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.B FUTEX_WAIT_BITSET
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2012-08-13 12:50:26 +00:00
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operation was interrupted by a signal (see
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.BR signal (7))
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or a spurious wakeup.
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2012-08-13 12:25:13 +00:00
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.TP
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2004-11-03 13:51:07 +00:00
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.B EINVAL
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2015-01-13 14:12:14 +00:00
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The operation in
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.IR futex_op
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is one of those that employs a timeout, but the supplied
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2014-06-04 06:57:48 +00:00
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.I timeout
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argument was invalid
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.RI ( tv_sec
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was less than zero, or
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.IR tv_nsec
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was not less than 1000,000,000).
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.TP
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.B EINVAL
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2015-01-13 13:48:03 +00:00
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The operation specified in
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.BR futex_op
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employs one or both of the pointers
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2014-06-04 07:22:41 +00:00
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.I uaddr
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2014-06-04 08:25:57 +00:00
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and
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2015-01-13 13:48:03 +00:00
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.IR uaddr2 ,
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but one of these does not point to a valid object\(emthat is,
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the address is not four-byte-aligned.
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2014-06-04 07:22:41 +00:00
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.TP
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.B EINVAL
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2014-06-04 08:12:47 +00:00
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.RB ( FUTEX_WAKE ,
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2015-01-13 14:56:55 +00:00
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.BR FUTEX_WAKE_OP ,
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2015-01-13 14:48:51 +00:00
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.BR FUTEX_WAKE_BITSET ,
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2014-06-04 08:28:29 +00:00
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.BR FUTEX_REQUEUE ,
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.BR FUTEX_CMP_REQUEUE )
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2014-06-04 07:39:08 +00:00
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The kernel detected an inconsistency between the user-space state at
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2014-06-04 07:36:45 +00:00
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.I uaddr
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and the kernel state\(emthat is, it detected a waiter which waits in
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2015-01-13 14:56:55 +00:00
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.BR FUTEX_LOCK_PI
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on
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.IR uaddr .
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2014-06-04 07:36:45 +00:00
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.TP
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.B EINVAL
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2015-01-13 14:36:37 +00:00
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.RB ( FUTEX_WAIT_BITSET ,
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.BR FUTEX_WAKE_BITSET )
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2015-01-13 14:34:17 +00:00
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The bitset supplied in
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.IR val3
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is zero.
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.TP
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.B EINVAL
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2014-06-04 08:16:52 +00:00
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.RB ( FUTEX_REQUEUE )
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.\" FIXME tglx suggested adding this, but does this error really
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.\" occur for FUTEX_REQUEUE?
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.I uaddr
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equals
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.IR uaddr2
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(i.e., an attempt was made to requeue to the same futex).
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.TP
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2015-01-13 09:11:46 +00:00
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.BR EINVAL
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.RB ( FUTEX_FD )
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The signal number supplied in
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.I val
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is invalid.
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.TP
|
2015-01-12 14:38:13 +00:00
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.B EINVAL
|
2012-08-13 12:51:22 +00:00
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Invalid argument.
|
2004-11-03 13:51:07 +00:00
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.TP
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.B ENFILE
|
2015-01-13 09:11:46 +00:00
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.RB ( FUTEX_FD )
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2004-11-03 13:51:07 +00:00
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The system limit on the total number of open files has been reached.
|
2008-01-31 10:35:05 +00:00
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.TP
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.B ENOSYS
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Invalid operation specified in
|
2015-01-12 14:40:43 +00:00
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.IR futex_op .
|
2012-08-13 12:25:13 +00:00
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.TP
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2015-01-12 11:52:28 +00:00
|
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.B ENOSYS
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The
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.BR FUTEX_CLOCK_REALTIME
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option was specified in
|
2015-01-13 13:53:51 +00:00
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.IR futex_op ,
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2015-01-12 11:52:28 +00:00
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but the accompanying operation was neither
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.BR FUTEX_WAIT_BITSET
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nor
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.BR FUTEX_WAIT_REQUEUE_PI .
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|
|
.TP
|
2012-08-13 12:25:13 +00:00
|
|
|
.B ETIMEDOUT
|
2015-01-13 13:52:53 +00:00
|
|
|
The operation in
|
|
|
|
.IR futex_op
|
|
|
|
employed the timeout specified in
|
|
|
|
.IR timeout ,
|
|
|
|
and the timeout expired before the operation completed.
|
2012-08-13 12:25:13 +00:00
|
|
|
.TP
|
|
|
|
.B EWOULDBLOCK
|
2015-01-13 13:56:12 +00:00
|
|
|
.RB ( FUTEX_WAIT )
|
|
|
|
The value pointed to by
|
2012-08-13 12:25:13 +00:00
|
|
|
.I uaddr
|
|
|
|
was not equal to the expected value
|
|
|
|
.I val
|
2012-08-13 12:50:26 +00:00
|
|
|
at the time of the call.
|
getent.1, intro.1, time.1, _exit.2, _syscall.2, accept.2, access.2, acct.2, adjtimex.2, alarm.2, alloc_hugepages.2, arch_prctl.2, bdflush.2, bind.2, brk.2, cacheflush.2, capget.2, chdir.2, chmod.2, chown.2, chroot.2, clock_getres.2, clock_nanosleep.2, clone.2, close.2, connect.2, create_module.2, delete_module.2, dup.2, epoll_create.2, epoll_ctl.2, epoll_wait.2, eventfd.2, execve.2, exit_group.2, faccessat.2, fchmodat.2, fchownat.2, fcntl.2, flock.2, fork.2, fstatat.2, fsync.2, futex.2, futimesat.2, get_kernel_syms.2, get_robust_list.2, get_thread_area.2, getcpu.2, getdents.2, getdomainname.2, getgid.2, getgroups.2, gethostname.2, getitimer.2, getpagesize.2, getpeername.2, getpid.2, getpriority.2, getresuid.2, getrlimit.2, getrusage.2, getsid.2, getsockname.2, getsockopt.2, gettid.2, gettimeofday.2, getuid.2, getunwind.2, getxattr.2, idle.2, init_module.2, inotify_add_watch.2, inotify_init.2, inotify_rm_watch.2, intro.2, io_cancel.2, io_destroy.2, io_getevents.2, io_setup.2, io_submit.2, ioctl.2, ioctl_list.2, ioperm.2, iopl.2, ioprio_set.2, ipc.2, kcmp.2, kill.2, killpg.2, link.2, linkat.2, listen.2, listxattr.2, llseek.2, lookup_dcookie.2, lseek.2, madvise.2, migrate_pages.2, mincore.2, mkdir.2, mkdirat.2, mknod.2, mknodat.2, mlock.2, mmap.2, mmap2.2, modify_ldt.2, mount.2, move_pages.2, mprotect.2, mq_getsetattr.2, mremap.2, msgctl.2, msgget.2, msgop.2, msync.2, nanosleep.2, nfsservctl.2, nice.2, open.2, openat.2, outb.2, pause.2, pciconfig_read.2, perf_event_open.2, perfmonctl.2, personality.2, pipe.2, pivot_root.2, poll.2, posix_fadvise.2, prctl.2, pread.2, process_vm_readv.2, ptrace.2, query_module.2, quotactl.2, read.2, readahead.2, readdir.2, readlink.2, readlinkat.2, readv.2, reboot.2, recv.2, remap_file_pages.2, removexattr.2, rename.2, renameat.2, rmdir.2, rt_sigqueueinfo.2, sched_get_priority_max.2, sched_rr_get_interval.2, sched_setaffinity.2, sched_setparam.2, sched_setscheduler.2, sched_yield.2, select.2, semctl.2, semget.2, semop.2, send.2, sendfile.2, set_thread_area.2, set_tid_address.2, seteuid.2, setfsgid.2, setfsuid.2, setgid.2, setpgid.2, setresuid.2, setreuid.2, setsid.2, setuid.2, setup.2, setxattr.2, shmctl.2, shmget.2, shmop.2, shutdown.2, sigaction.2, sigaltstack.2, signal.2, signalfd.2, sigpending.2, sigprocmask.2, sigreturn.2, sigsuspend.2, sigwaitinfo.2, socket.2, socketcall.2, socketpair.2, splice.2, stat.2, statfs.2, stime.2, swapon.2, symlink.2, symlinkat.2, sync.2, sync_file_range.2, sysctl.2, sysfs.2, sysinfo.2, syslog.2, tee.2, time.2, timerfd_create.2, times.2, tkill.2, truncate.2, umask.2, umount.2, uname.2, unimplemented.2, unlink.2, unlinkat.2, uselib.2, ustat.2, utime.2, utimensat.2, vfork.2, vhangup.2, vm86.2, vmsplice.2, wait.2, wait4.2, write.2, CPU_SET.3, INFINITY.3, MB_CUR_MAX.3, MB_LEN_MAX.3, __setfpucw.3, a64l.3, abort.3, abs.3, acos.3, acosh.3, addseverity.3, adjtime.3, aio_cancel.3, aio_error.3, aio_fsync.3, aio_read.3, aio_return.3, aio_suspend.3, aio_write.3, alloca.3, argz_add.3, asin.3, asinh.3, asprintf.3, assert.3, assert_perror.3, atan.3, atan2.3, atanh.3, atexit.3, atof.3, atoi.3, backtrace.3, basename.3, bcmp.3, bcopy.3, bindresvport.3, bsd_signal.3, bsearch.3, bstring.3, btowc.3, btree.3, byteorder.3, bzero.3, cabs.3, cacos.3, cacosh.3, canonicalize_file_name.3, carg.3, casin.3, casinh.3, catan.3, catanh.3, catgets.3, catopen.3, cbrt.3, ccos.3, ccosh.3, ceil.3, cerf.3, cexp.3, cexp2.3, cfree.3, cimag.3, clearenv.3, clock.3, clock_getcpuclockid.3, clog.3, clog10.3, clog2.3, closedir.3, cmsg.3, confstr.3, conj.3, copysign.3, cos.3, cosh.3, cpow.3, cproj.3, creal.3, crypt.3, csin.3, csinh.3, csqrt.3, ctan.3, ctanh.3, ctermid.3, ctime.3, daemon.3, dbopen.3, des_crypt.3, difftime.3, dirfd.3, div.3, dl_iterate_phdr.3, dlopen.3, dprintf.3, drand48.3, drand48_r.3, dysize.3, ecvt.3, ecvt_r.3, encrypt.3, end.3, endian.3, envz_add.3, erf.3, erfc.3, err.3, errno.3, error.3, ether_aton.3, euidaccess.3, exec.3, exit.3, exp.3, exp10.3, exp2.3, expm1.3, fabs.3, fclose.3, fcloseall.3, fdim.3, fenv.3, ferror.3, fexecve.3, fflush.3, ffs.3, fgetgrent.3, fgetpwent.3, fgetwc.3, fgetws.3, finite.3, flockfile.3, floor.3, fma.3, fmax.3, fmemopen.3, fmin.3, fmod.3, fmtmsg.3, fnmatch.3, fopen.3, fpathconf.3, fpclassify.3, fpurge.3, fputwc.3, fputws.3, fread.3, frexp.3, fseek.3, fseeko.3, ftime.3, ftok.3, fts.3, ftw.3, futimes.3, fwide.3, gamma.3, gcvt.3, getaddrinfo.3, getaddrinfo_a.3, getauxval.3, getcontext.3, getcwd.3, getdate.3, getdirentries.3, getdtablesize.3, getenv.3, getfsent.3, getgrent.3, getgrent_r.3, getgrnam.3, getgrouplist.3, gethostbyname.3, gethostid.3, getipnodebyname.3, getline.3, getloadavg.3, getlogin.3, getmntent.3, getnameinfo.3, getnetent.3, getnetent_r.3, getopt.3, getpass.3, getprotoent.3, getprotoent_r.3, getpt.3, getpw.3, getpwent.3, getpwent_r.3, getpwnam.3, getrpcent.3, getrpcent_r.3, getrpcport.3, gets.3, getservent.3, getservent_r.3, getspnam.3, getttyent.3, getumask.3, getusershell.3, getutent.3, getw.3, getwchar.3, glob.3, grantpt.3, gsignal.3, hash.3, hsearch.3, hypot.3, iconv.3, iconv_close.3, iconv_open.3, ilogb.3, index.3, inet.3, inet_ntop.3, inet_pton.3, infnan.3, initgroups.3, insque.3, intro.3, isalpha.3, isatty.3, isgreater.3, iswalnum.3, iswalpha.3, iswblank.3, iswcntrl.3, iswctype.3, iswdigit.3, iswgraph.3, iswlower.3, iswprint.3, iswpunct.3, iswspace.3, iswupper.3, iswxdigit.3, j0.3, key_setsecret.3, ldexp.3, lgamma.3, lio_listio.3, localeconv.3, lockf.3, log.3, log10.3, log1p.3, log2.3, logb.3, login.3, longjmp.3, lrint.3, lround.3, lsearch.3, lseek64.3, makecontext.3, makedev.3, malloc.3, malloc_hook.3, mblen.3, mbrlen.3, mbrtowc.3, mbsinit.3, mbsnrtowcs.3, mbsrtowcs.3, mbstowcs.3, mbtowc.3, memccpy.3, memchr.3, memcmp.3, memcpy.3, memfrob.3, memmem.3, memmove.3, mempcpy.3, memset.3, mkdtemp.3, mkfifo.3, mkfifoat.3, mkstemp.3, mktemp.3, modf.3, mpool.3, mq_close.3, mq_getattr.3, mq_notify.3, mq_open.3, mq_receive.3, mq_send.3, mq_unlink.3, mtrace.3, nan.3, netlink.3, nextafter.3, nl_langinfo.3, offsetof.3, on_exit.3, opendir.3, openpty.3, perror.3, popen.3, posix_fallocate.3, posix_memalign.3, posix_openpt.3, pow.3, pow10.3, printf.3, profil.3, program_invocation_name.3, psignal.3, pthread_kill_other_threads_np.3, ptsname.3, putenv.3, putgrent.3, putpwent.3, puts.3, putwchar.3, qecvt.3, qsort.3, queue.3, raise.3, rand.3, random.3, random_r.3, rcmd.3, re_comp.3, readdir.3, realpath.3, recno.3, regex.3, remainder.3, remove.3, remquo.3, resolver.3, rewinddir.3, rexec.3, rint.3, round.3, rpc.3, rpmatch.3, rtime.3, rtnetlink.3, scalb.3, scalbln.3, scandir.3, scandirat.3, scanf.3, seekdir.3, sem_close.3, sem_destroy.3, sem_getvalue.3, sem_init.3, sem_open.3, sem_post.3, sem_unlink.3, sem_wait.3, setaliasent.3, setbuf.3, setenv.3, setjmp.3, setlocale.3, setlogmask.3, setnetgrent.3, shm_open.3, siginterrupt.3, signbit.3, significand.3, sigpause.3, sigqueue.3, sigset.3, sigsetops.3, sigvec.3, sin.3, sincos.3, sinh.3, sleep.3, sockatmark.3, sqrt.3, statvfs.3, stdarg.3, stdin.3, stdio.3, stdio_ext.3, stpcpy.3, stpncpy.3, strcasecmp.3, strcat.3, strchr.3, strcmp.3, strcoll.3, strcpy.3, strdup.3, strerror.3, strfmon.3, strfry.3, strftime.3, string.3, strlen.3, strnlen.3, strpbrk.3, strptime.3, strsep.3, strsignal.3, strspn.3, strstr.3, strtod.3, strtoimax.3, strtok.3, strtol.3, strtoul.3, strverscmp.3, strxfrm.3, swab.3, sysconf.3, syslog.3, system.3, sysv_signal.3, tan.3, tanh.3, tcgetpgrp.3, tcgetsid.3, telldir.3, tempnam.3, termios.3, tgamma.3, timegm.3, timeradd.3, tmpfile.3, tmpnam.3, toascii.3, toupper.3, towctrans.3, towlower.3, towupper.3, trunc.3, tsearch.3, ttyname.3, ttyslot.3, tzset.3, ualarm.3, ulimit.3, ungetwc.3, unlocked_stdio.3, unlockpt.3, updwtmp.3, usleep.3, wcpcpy.3, wcpncpy.3, wcrtomb.3, wcscasecmp.3, wcscat.3, wcschr.3, wcscmp.3, wcscpy.3, wcscspn.3, wcsdup.3, wcslen.3, wcsncasecmp.3, wcsncat.3, wcsncmp.3, wcsncpy.3, wcsnlen.3, wcsnrtombs.3, wcspbrk.3, wcsrchr.3, wcsrtombs.3, wcsspn.3, wcsstr.3, wcstoimax.3, wcstok.3, wcstombs.3, wcswidth.3, wctob.3, wctomb.3, wctrans.3, wctype.3, wcwidth.3, wmemchr.3, wmemcmp.3, wmemcpy.3, wmemmove.3, wmemset.3, wordexp.3, wprintf.3, xcrypt.3, xdr.3, y0.3, cciss.4, console.4, console_codes.4, console_ioctl.4, dsp56k.4, fd.4, full.4, hd.4, hpsa.4, initrd.4, intro.4, lp.4, mem.4, mouse.4, null.4, pts.4, ram.4, random.4, rtc.4, sk98lin.4, st.4, tty.4, ttyS.4, tty_ioctl.4, vcs.4, wavelan.4, acct.5, charmap.5, dir_colors.5, filesystems.5, ftpusers.5, group.5, host.conf.5, hosts.5, hosts.equiv.5, intro.5, issue.5, locale.5, motd.5, networks.5, nologin.5, nscd.conf.5, passwd.5, proc.5, protocols.5, resolv.conf.5, rpc.5, securetty.5, services.5, shells.5, termcap.5, ttytype.5, utmp.5, armscii-8.7, arp.7, ascii.7, bootparam.7, capabilities.7, charsets.7, complex.7, cp1251.7, credentials.7, ddp.7, environ.7, epoll.7, fifo.7, futex.7, glob.7, hier.7, icmp.7, inotify.7, intro.7, ip.7, ipv6.7, iso_8859-1.7, iso_8859-10.7, iso_8859-11.7, iso_8859-13.7, iso_8859-14.7, iso_8859-15.7, iso_8859-16.7, iso_8859-2.7, iso_8859-3.7, iso_8859-4.7, iso_8859-5.7, iso_8859-6.7, iso_8859-7.7, iso_8859-8.7, iso_8859-9.7, koi8-r.7, koi8-u.7, locale.7, mailaddr.7, man.7, mq_overview.7, netdevice.7, netlink.7, numa.7, packet.7, path_resolution.7, pipe.7, posixoptions.7, pthreads.7, pty.7, raw.7, regex.7, rtld-audit.7, rtnetlink.7, sem_overview.7, shm_overview.7, sigevent.7, signal.7, socket.7, standards.7, suffixes.7, svipc.7, tcp.7, termio.7, time.7, udp.7, udplite.7, unicode.7, unix.7, uri.7, utf-8.7, x25.7, nscd.8, sync.8, tzselect.8, zdump.8, zic.8: Global fix: remove unneeded double quotes in .SH headings
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-02-24 18:01:36 +00:00
|
|
|
.SH VERSIONS
|
2007-05-18 16:06:42 +00:00
|
|
|
.PP
|
2015-01-12 12:24:43 +00:00
|
|
|
Futexes were first made available in a stable kernel release
|
|
|
|
with Linux 2.6.0.
|
|
|
|
|
2007-05-18 16:06:42 +00:00
|
|
|
Initial futex support was merged in Linux 2.5.7 but with different semantics
|
|
|
|
from what was described above.
|
2015-01-13 14:14:12 +00:00
|
|
|
A four-argument system call with the semantics
|
2010-08-29 04:21:27 +00:00
|
|
|
described in this page was introduced in Linux 2.5.40.
|
2014-04-23 14:40:46 +00:00
|
|
|
In Linux 2.5.70, one argument
|
2007-05-18 16:06:42 +00:00
|
|
|
was added.
|
2014-04-23 14:40:46 +00:00
|
|
|
In Linux 2.6.7, a sixth argument was added\(emmessy, especially
|
2007-05-18 16:06:42 +00:00
|
|
|
on the s390 architecture.
|
getent.1, intro.1, time.1, _exit.2, _syscall.2, accept.2, access.2, acct.2, adjtimex.2, alarm.2, alloc_hugepages.2, arch_prctl.2, bdflush.2, bind.2, brk.2, cacheflush.2, capget.2, chdir.2, chmod.2, chown.2, chroot.2, clock_getres.2, clock_nanosleep.2, clone.2, close.2, connect.2, create_module.2, delete_module.2, dup.2, epoll_create.2, epoll_ctl.2, epoll_wait.2, eventfd.2, execve.2, exit_group.2, faccessat.2, fchmodat.2, fchownat.2, fcntl.2, flock.2, fork.2, fstatat.2, fsync.2, futex.2, futimesat.2, get_kernel_syms.2, get_robust_list.2, get_thread_area.2, getcpu.2, getdents.2, getdomainname.2, getgid.2, getgroups.2, gethostname.2, getitimer.2, getpagesize.2, getpeername.2, getpid.2, getpriority.2, getresuid.2, getrlimit.2, getrusage.2, getsid.2, getsockname.2, getsockopt.2, gettid.2, gettimeofday.2, getuid.2, getunwind.2, getxattr.2, idle.2, init_module.2, inotify_add_watch.2, inotify_init.2, inotify_rm_watch.2, intro.2, io_cancel.2, io_destroy.2, io_getevents.2, io_setup.2, io_submit.2, ioctl.2, ioctl_list.2, ioperm.2, iopl.2, ioprio_set.2, ipc.2, kcmp.2, kill.2, killpg.2, link.2, linkat.2, listen.2, listxattr.2, llseek.2, lookup_dcookie.2, lseek.2, madvise.2, migrate_pages.2, mincore.2, mkdir.2, mkdirat.2, mknod.2, mknodat.2, mlock.2, mmap.2, mmap2.2, modify_ldt.2, mount.2, move_pages.2, mprotect.2, mq_getsetattr.2, mremap.2, msgctl.2, msgget.2, msgop.2, msync.2, nanosleep.2, nfsservctl.2, nice.2, open.2, openat.2, outb.2, pause.2, pciconfig_read.2, perf_event_open.2, perfmonctl.2, personality.2, pipe.2, pivot_root.2, poll.2, posix_fadvise.2, prctl.2, pread.2, process_vm_readv.2, ptrace.2, query_module.2, quotactl.2, read.2, readahead.2, readdir.2, readlink.2, readlinkat.2, readv.2, reboot.2, recv.2, remap_file_pages.2, removexattr.2, rename.2, renameat.2, rmdir.2, rt_sigqueueinfo.2, sched_get_priority_max.2, sched_rr_get_interval.2, sched_setaffinity.2, sched_setparam.2, sched_setscheduler.2, sched_yield.2, select.2, semctl.2, semget.2, semop.2, send.2, sendfile.2, set_thread_area.2, set_tid_address.2, seteuid.2, setfsgid.2, setfsuid.2, setgid.2, setpgid.2, setresuid.2, setreuid.2, setsid.2, setuid.2, setup.2, setxattr.2, shmctl.2, shmget.2, shmop.2, shutdown.2, sigaction.2, sigaltstack.2, signal.2, signalfd.2, sigpending.2, sigprocmask.2, sigreturn.2, sigsuspend.2, sigwaitinfo.2, socket.2, socketcall.2, socketpair.2, splice.2, stat.2, statfs.2, stime.2, swapon.2, symlink.2, symlinkat.2, sync.2, sync_file_range.2, sysctl.2, sysfs.2, sysinfo.2, syslog.2, tee.2, time.2, timerfd_create.2, times.2, tkill.2, truncate.2, umask.2, umount.2, uname.2, unimplemented.2, unlink.2, unlinkat.2, uselib.2, ustat.2, utime.2, utimensat.2, vfork.2, vhangup.2, vm86.2, vmsplice.2, wait.2, wait4.2, write.2, CPU_SET.3, INFINITY.3, MB_CUR_MAX.3, MB_LEN_MAX.3, __setfpucw.3, a64l.3, abort.3, abs.3, acos.3, acosh.3, addseverity.3, adjtime.3, aio_cancel.3, aio_error.3, aio_fsync.3, aio_read.3, aio_return.3, aio_suspend.3, aio_write.3, alloca.3, argz_add.3, asin.3, asinh.3, asprintf.3, assert.3, assert_perror.3, atan.3, atan2.3, atanh.3, atexit.3, atof.3, atoi.3, backtrace.3, basename.3, bcmp.3, bcopy.3, bindresvport.3, bsd_signal.3, bsearch.3, bstring.3, btowc.3, btree.3, byteorder.3, bzero.3, cabs.3, cacos.3, cacosh.3, canonicalize_file_name.3, carg.3, casin.3, casinh.3, catan.3, catanh.3, catgets.3, catopen.3, cbrt.3, ccos.3, ccosh.3, ceil.3, cerf.3, cexp.3, cexp2.3, cfree.3, cimag.3, clearenv.3, clock.3, clock_getcpuclockid.3, clog.3, clog10.3, clog2.3, closedir.3, cmsg.3, confstr.3, conj.3, copysign.3, cos.3, cosh.3, cpow.3, cproj.3, creal.3, crypt.3, csin.3, csinh.3, csqrt.3, ctan.3, ctanh.3, ctermid.3, ctime.3, daemon.3, dbopen.3, des_crypt.3, difftime.3, dirfd.3, div.3, dl_iterate_phdr.3, dlopen.3, dprintf.3, drand48.3, drand48_r.3, dysize.3, ecvt.3, ecvt_r.3, encrypt.3, end.3, endian.3, envz_add.3, erf.3, erfc.3, err.3, errno.3, error.3, ether_aton.3, euidaccess.3, exec.3, exit.3, exp.3, exp10.3, exp2.3, expm1.3, fabs.3, fclose.3, fcloseall.3, fdim.3, fenv.3, ferror.3, fexecve.3, fflush.3, ffs.3, fgetgrent.3, fgetpwent.3, fgetwc.3, fgetws.3, finite.3, flockfile.3, floor.3, fma.3, fmax.3, fmemopen.3, fmin.3, fmod.3, fmtmsg.3, fnmatch.3, fopen.3, fpathconf.3, fpclassify.3, fpurge.3, fputwc.3, fputws.3, fread.3, frexp.3, fseek.3, fseeko.3, ftime.3, ftok.3, fts.3, ftw.3, futimes.3, fwide.3, gamma.3, gcvt.3, getaddrinfo.3, getaddrinfo_a.3, getauxval.3, getcontext.3, getcwd.3, getdate.3, getdirentries.3, getdtablesize.3, getenv.3, getfsent.3, getgrent.3, getgrent_r.3, getgrnam.3, getgrouplist.3, gethostbyname.3, gethostid.3, getipnodebyname.3, getline.3, getloadavg.3, getlogin.3, getmntent.3, getnameinfo.3, getnetent.3, getnetent_r.3, getopt.3, getpass.3, getprotoent.3, getprotoent_r.3, getpt.3, getpw.3, getpwent.3, getpwent_r.3, getpwnam.3, getrpcent.3, getrpcent_r.3, getrpcport.3, gets.3, getservent.3, getservent_r.3, getspnam.3, getttyent.3, getumask.3, getusershell.3, getutent.3, getw.3, getwchar.3, glob.3, grantpt.3, gsignal.3, hash.3, hsearch.3, hypot.3, iconv.3, iconv_close.3, iconv_open.3, ilogb.3, index.3, inet.3, inet_ntop.3, inet_pton.3, infnan.3, initgroups.3, insque.3, intro.3, isalpha.3, isatty.3, isgreater.3, iswalnum.3, iswalpha.3, iswblank.3, iswcntrl.3, iswctype.3, iswdigit.3, iswgraph.3, iswlower.3, iswprint.3, iswpunct.3, iswspace.3, iswupper.3, iswxdigit.3, j0.3, key_setsecret.3, ldexp.3, lgamma.3, lio_listio.3, localeconv.3, lockf.3, log.3, log10.3, log1p.3, log2.3, logb.3, login.3, longjmp.3, lrint.3, lround.3, lsearch.3, lseek64.3, makecontext.3, makedev.3, malloc.3, malloc_hook.3, mblen.3, mbrlen.3, mbrtowc.3, mbsinit.3, mbsnrtowcs.3, mbsrtowcs.3, mbstowcs.3, mbtowc.3, memccpy.3, memchr.3, memcmp.3, memcpy.3, memfrob.3, memmem.3, memmove.3, mempcpy.3, memset.3, mkdtemp.3, mkfifo.3, mkfifoat.3, mkstemp.3, mktemp.3, modf.3, mpool.3, mq_close.3, mq_getattr.3, mq_notify.3, mq_open.3, mq_receive.3, mq_send.3, mq_unlink.3, mtrace.3, nan.3, netlink.3, nextafter.3, nl_langinfo.3, offsetof.3, on_exit.3, opendir.3, openpty.3, perror.3, popen.3, posix_fallocate.3, posix_memalign.3, posix_openpt.3, pow.3, pow10.3, printf.3, profil.3, program_invocation_name.3, psignal.3, pthread_kill_other_threads_np.3, ptsname.3, putenv.3, putgrent.3, putpwent.3, puts.3, putwchar.3, qecvt.3, qsort.3, queue.3, raise.3, rand.3, random.3, random_r.3, rcmd.3, re_comp.3, readdir.3, realpath.3, recno.3, regex.3, remainder.3, remove.3, remquo.3, resolver.3, rewinddir.3, rexec.3, rint.3, round.3, rpc.3, rpmatch.3, rtime.3, rtnetlink.3, scalb.3, scalbln.3, scandir.3, scandirat.3, scanf.3, seekdir.3, sem_close.3, sem_destroy.3, sem_getvalue.3, sem_init.3, sem_open.3, sem_post.3, sem_unlink.3, sem_wait.3, setaliasent.3, setbuf.3, setenv.3, setjmp.3, setlocale.3, setlogmask.3, setnetgrent.3, shm_open.3, siginterrupt.3, signbit.3, significand.3, sigpause.3, sigqueue.3, sigset.3, sigsetops.3, sigvec.3, sin.3, sincos.3, sinh.3, sleep.3, sockatmark.3, sqrt.3, statvfs.3, stdarg.3, stdin.3, stdio.3, stdio_ext.3, stpcpy.3, stpncpy.3, strcasecmp.3, strcat.3, strchr.3, strcmp.3, strcoll.3, strcpy.3, strdup.3, strerror.3, strfmon.3, strfry.3, strftime.3, string.3, strlen.3, strnlen.3, strpbrk.3, strptime.3, strsep.3, strsignal.3, strspn.3, strstr.3, strtod.3, strtoimax.3, strtok.3, strtol.3, strtoul.3, strverscmp.3, strxfrm.3, swab.3, sysconf.3, syslog.3, system.3, sysv_signal.3, tan.3, tanh.3, tcgetpgrp.3, tcgetsid.3, telldir.3, tempnam.3, termios.3, tgamma.3, timegm.3, timeradd.3, tmpfile.3, tmpnam.3, toascii.3, toupper.3, towctrans.3, towlower.3, towupper.3, trunc.3, tsearch.3, ttyname.3, ttyslot.3, tzset.3, ualarm.3, ulimit.3, ungetwc.3, unlocked_stdio.3, unlockpt.3, updwtmp.3, usleep.3, wcpcpy.3, wcpncpy.3, wcrtomb.3, wcscasecmp.3, wcscat.3, wcschr.3, wcscmp.3, wcscpy.3, wcscspn.3, wcsdup.3, wcslen.3, wcsncasecmp.3, wcsncat.3, wcsncmp.3, wcsncpy.3, wcsnlen.3, wcsnrtombs.3, wcspbrk.3, wcsrchr.3, wcsrtombs.3, wcsspn.3, wcsstr.3, wcstoimax.3, wcstok.3, wcstombs.3, wcswidth.3, wctob.3, wctomb.3, wctrans.3, wctype.3, wcwidth.3, wmemchr.3, wmemcmp.3, wmemcpy.3, wmemmove.3, wmemset.3, wordexp.3, wprintf.3, xcrypt.3, xdr.3, y0.3, cciss.4, console.4, console_codes.4, console_ioctl.4, dsp56k.4, fd.4, full.4, hd.4, hpsa.4, initrd.4, intro.4, lp.4, mem.4, mouse.4, null.4, pts.4, ram.4, random.4, rtc.4, sk98lin.4, st.4, tty.4, ttyS.4, tty_ioctl.4, vcs.4, wavelan.4, acct.5, charmap.5, dir_colors.5, filesystems.5, ftpusers.5, group.5, host.conf.5, hosts.5, hosts.equiv.5, intro.5, issue.5, locale.5, motd.5, networks.5, nologin.5, nscd.conf.5, passwd.5, proc.5, protocols.5, resolv.conf.5, rpc.5, securetty.5, services.5, shells.5, termcap.5, ttytype.5, utmp.5, armscii-8.7, arp.7, ascii.7, bootparam.7, capabilities.7, charsets.7, complex.7, cp1251.7, credentials.7, ddp.7, environ.7, epoll.7, fifo.7, futex.7, glob.7, hier.7, icmp.7, inotify.7, intro.7, ip.7, ipv6.7, iso_8859-1.7, iso_8859-10.7, iso_8859-11.7, iso_8859-13.7, iso_8859-14.7, iso_8859-15.7, iso_8859-16.7, iso_8859-2.7, iso_8859-3.7, iso_8859-4.7, iso_8859-5.7, iso_8859-6.7, iso_8859-7.7, iso_8859-8.7, iso_8859-9.7, koi8-r.7, koi8-u.7, locale.7, mailaddr.7, man.7, mq_overview.7, netdevice.7, netlink.7, numa.7, packet.7, path_resolution.7, pipe.7, posixoptions.7, pthreads.7, pty.7, raw.7, regex.7, rtld-audit.7, rtnetlink.7, sem_overview.7, shm_overview.7, sigevent.7, signal.7, socket.7, standards.7, suffixes.7, svipc.7, tcp.7, termio.7, time.7, udp.7, udplite.7, unicode.7, unix.7, uri.7, utf-8.7, x25.7, nscd.8, sync.8, tzselect.8, zdump.8, zic.8: Global fix: remove unneeded double quotes in .SH headings
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-02-24 18:01:36 +00:00
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.SH CONFORMING TO
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2007-12-25 21:28:09 +00:00
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This system call is Linux-specific.
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getent.1, intro.1, time.1, _exit.2, _syscall.2, accept.2, access.2, acct.2, adjtimex.2, alarm.2, alloc_hugepages.2, arch_prctl.2, bdflush.2, bind.2, brk.2, cacheflush.2, capget.2, chdir.2, chmod.2, chown.2, chroot.2, clock_getres.2, clock_nanosleep.2, clone.2, close.2, connect.2, create_module.2, delete_module.2, dup.2, epoll_create.2, epoll_ctl.2, epoll_wait.2, eventfd.2, execve.2, exit_group.2, faccessat.2, fchmodat.2, fchownat.2, fcntl.2, flock.2, fork.2, fstatat.2, fsync.2, futex.2, futimesat.2, get_kernel_syms.2, get_robust_list.2, get_thread_area.2, getcpu.2, getdents.2, getdomainname.2, getgid.2, getgroups.2, gethostname.2, getitimer.2, getpagesize.2, getpeername.2, getpid.2, getpriority.2, getresuid.2, getrlimit.2, getrusage.2, getsid.2, getsockname.2, getsockopt.2, gettid.2, gettimeofday.2, getuid.2, getunwind.2, getxattr.2, idle.2, init_module.2, inotify_add_watch.2, inotify_init.2, inotify_rm_watch.2, intro.2, io_cancel.2, io_destroy.2, io_getevents.2, io_setup.2, io_submit.2, ioctl.2, ioctl_list.2, ioperm.2, iopl.2, ioprio_set.2, ipc.2, kcmp.2, kill.2, killpg.2, link.2, linkat.2, listen.2, listxattr.2, llseek.2, lookup_dcookie.2, lseek.2, madvise.2, migrate_pages.2, mincore.2, mkdir.2, mkdirat.2, mknod.2, mknodat.2, mlock.2, mmap.2, mmap2.2, modify_ldt.2, mount.2, move_pages.2, mprotect.2, mq_getsetattr.2, mremap.2, msgctl.2, msgget.2, msgop.2, msync.2, nanosleep.2, nfsservctl.2, nice.2, open.2, openat.2, outb.2, pause.2, pciconfig_read.2, perf_event_open.2, perfmonctl.2, personality.2, pipe.2, pivot_root.2, poll.2, posix_fadvise.2, prctl.2, pread.2, process_vm_readv.2, ptrace.2, query_module.2, quotactl.2, read.2, readahead.2, readdir.2, readlink.2, readlinkat.2, readv.2, reboot.2, recv.2, remap_file_pages.2, removexattr.2, rename.2, renameat.2, rmdir.2, rt_sigqueueinfo.2, sched_get_priority_max.2, sched_rr_get_interval.2, sched_setaffinity.2, sched_setparam.2, sched_setscheduler.2, sched_yield.2, select.2, semctl.2, semget.2, semop.2, send.2, sendfile.2, set_thread_area.2, set_tid_address.2, seteuid.2, setfsgid.2, setfsuid.2, setgid.2, setpgid.2, setresuid.2, setreuid.2, setsid.2, setuid.2, setup.2, setxattr.2, shmctl.2, shmget.2, shmop.2, shutdown.2, sigaction.2, sigaltstack.2, signal.2, signalfd.2, sigpending.2, sigprocmask.2, sigreturn.2, sigsuspend.2, sigwaitinfo.2, socket.2, socketcall.2, socketpair.2, splice.2, stat.2, statfs.2, stime.2, swapon.2, symlink.2, symlinkat.2, sync.2, sync_file_range.2, sysctl.2, sysfs.2, sysinfo.2, syslog.2, tee.2, time.2, timerfd_create.2, times.2, tkill.2, truncate.2, umask.2, umount.2, uname.2, unimplemented.2, unlink.2, unlinkat.2, uselib.2, ustat.2, utime.2, utimensat.2, vfork.2, vhangup.2, vm86.2, vmsplice.2, wait.2, wait4.2, write.2, CPU_SET.3, INFINITY.3, MB_CUR_MAX.3, MB_LEN_MAX.3, __setfpucw.3, a64l.3, abort.3, abs.3, acos.3, acosh.3, addseverity.3, adjtime.3, aio_cancel.3, aio_error.3, aio_fsync.3, aio_read.3, aio_return.3, aio_suspend.3, aio_write.3, alloca.3, argz_add.3, asin.3, asinh.3, asprintf.3, assert.3, assert_perror.3, atan.3, atan2.3, atanh.3, atexit.3, atof.3, atoi.3, backtrace.3, basename.3, bcmp.3, bcopy.3, bindresvport.3, bsd_signal.3, bsearch.3, bstring.3, btowc.3, btree.3, byteorder.3, bzero.3, cabs.3, cacos.3, cacosh.3, canonicalize_file_name.3, carg.3, casin.3, casinh.3, catan.3, catanh.3, catgets.3, catopen.3, cbrt.3, ccos.3, ccosh.3, ceil.3, cerf.3, cexp.3, cexp2.3, cfree.3, cimag.3, clearenv.3, clock.3, clock_getcpuclockid.3, clog.3, clog10.3, clog2.3, closedir.3, cmsg.3, confstr.3, conj.3, copysign.3, cos.3, cosh.3, cpow.3, cproj.3, creal.3, crypt.3, csin.3, csinh.3, csqrt.3, ctan.3, ctanh.3, ctermid.3, ctime.3, daemon.3, dbopen.3, des_crypt.3, difftime.3, dirfd.3, div.3, dl_iterate_phdr.3, dlopen.3, dprintf.3, drand48.3, drand48_r.3, dysize.3, ecvt.3, ecvt_r.3, encrypt.3, end.3, endian.3, envz_add.3, erf.3, erfc.3, err.3, errno.3, error.3, ether_aton.3, euidaccess.3, exec.3, exit.3, exp.3, exp10.3, exp2.3, expm1.3, fabs.3, fclose.3, fcloseall.3, fdim.3, fenv.3, ferror.3, fexecve.3, fflush.3, ffs.3, fgetgrent.3, fgetpwent.3, fgetwc.3, fgetws.3, finite.3, flockfile.3, floor.3, fma.3, fmax.3, fmemopen.3, fmin.3, fmod.3, fmtmsg.3, fnmatch.3, fopen.3, fpathconf.3, fpclassify.3, fpurge.3, fputwc.3, fputws.3, fread.3, frexp.3, fseek.3, fseeko.3, ftime.3, ftok.3, fts.3, ftw.3, futimes.3, fwide.3, gamma.3, gcvt.3, getaddrinfo.3, getaddrinfo_a.3, getauxval.3, getcontext.3, getcwd.3, getdate.3, getdirentries.3, getdtablesize.3, getenv.3, getfsent.3, getgrent.3, getgrent_r.3, getgrnam.3, getgrouplist.3, gethostbyname.3, gethostid.3, getipnodebyname.3, getline.3, getloadavg.3, getlogin.3, getmntent.3, getnameinfo.3, getnetent.3, getnetent_r.3, getopt.3, getpass.3, getprotoent.3, getprotoent_r.3, getpt.3, getpw.3, getpwent.3, getpwent_r.3, getpwnam.3, getrpcent.3, getrpcent_r.3, getrpcport.3, gets.3, getservent.3, getservent_r.3, getspnam.3, getttyent.3, getumask.3, getusershell.3, getutent.3, getw.3, getwchar.3, glob.3, grantpt.3, gsignal.3, hash.3, hsearch.3, hypot.3, iconv.3, iconv_close.3, iconv_open.3, ilogb.3, index.3, inet.3, inet_ntop.3, inet_pton.3, infnan.3, initgroups.3, insque.3, intro.3, isalpha.3, isatty.3, isgreater.3, iswalnum.3, iswalpha.3, iswblank.3, iswcntrl.3, iswctype.3, iswdigit.3, iswgraph.3, iswlower.3, iswprint.3, iswpunct.3, iswspace.3, iswupper.3, iswxdigit.3, j0.3, key_setsecret.3, ldexp.3, lgamma.3, lio_listio.3, localeconv.3, lockf.3, log.3, log10.3, log1p.3, log2.3, logb.3, login.3, longjmp.3, lrint.3, lround.3, lsearch.3, lseek64.3, makecontext.3, makedev.3, malloc.3, malloc_hook.3, mblen.3, mbrlen.3, mbrtowc.3, mbsinit.3, mbsnrtowcs.3, mbsrtowcs.3, mbstowcs.3, mbtowc.3, memccpy.3, memchr.3, memcmp.3, memcpy.3, memfrob.3, memmem.3, memmove.3, mempcpy.3, memset.3, mkdtemp.3, mkfifo.3, mkfifoat.3, mkstemp.3, mktemp.3, modf.3, mpool.3, mq_close.3, mq_getattr.3, mq_notify.3, mq_open.3, mq_receive.3, mq_send.3, mq_unlink.3, mtrace.3, nan.3, netlink.3, nextafter.3, nl_langinfo.3, offsetof.3, on_exit.3, opendir.3, openpty.3, perror.3, popen.3, posix_fallocate.3, posix_memalign.3, posix_openpt.3, pow.3, pow10.3, printf.3, profil.3, program_invocation_name.3, psignal.3, pthread_kill_other_threads_np.3, ptsname.3, putenv.3, putgrent.3, putpwent.3, puts.3, putwchar.3, qecvt.3, qsort.3, queue.3, raise.3, rand.3, random.3, random_r.3, rcmd.3, re_comp.3, readdir.3, realpath.3, recno.3, regex.3, remainder.3, remove.3, remquo.3, resolver.3, rewinddir.3, rexec.3, rint.3, round.3, rpc.3, rpmatch.3, rtime.3, rtnetlink.3, scalb.3, scalbln.3, scandir.3, scandirat.3, scanf.3, seekdir.3, sem_close.3, sem_destroy.3, sem_getvalue.3, sem_init.3, sem_open.3, sem_post.3, sem_unlink.3, sem_wait.3, setaliasent.3, setbuf.3, setenv.3, setjmp.3, setlocale.3, setlogmask.3, setnetgrent.3, shm_open.3, siginterrupt.3, signbit.3, significand.3, sigpause.3, sigqueue.3, sigset.3, sigsetops.3, sigvec.3, sin.3, sincos.3, sinh.3, sleep.3, sockatmark.3, sqrt.3, statvfs.3, stdarg.3, stdin.3, stdio.3, stdio_ext.3, stpcpy.3, stpncpy.3, strcasecmp.3, strcat.3, strchr.3, strcmp.3, strcoll.3, strcpy.3, strdup.3, strerror.3, strfmon.3, strfry.3, strftime.3, string.3, strlen.3, strnlen.3, strpbrk.3, strptime.3, strsep.3, strsignal.3, strspn.3, strstr.3, strtod.3, strtoimax.3, strtok.3, strtol.3, strtoul.3, strverscmp.3, strxfrm.3, swab.3, sysconf.3, syslog.3, system.3, sysv_signal.3, tan.3, tanh.3, tcgetpgrp.3, tcgetsid.3, telldir.3, tempnam.3, termios.3, tgamma.3, timegm.3, timeradd.3, tmpfile.3, tmpnam.3, toascii.3, toupper.3, towctrans.3, towlower.3, towupper.3, trunc.3, tsearch.3, ttyname.3, ttyslot.3, tzset.3, ualarm.3, ulimit.3, ungetwc.3, unlocked_stdio.3, unlockpt.3, updwtmp.3, usleep.3, wcpcpy.3, wcpncpy.3, wcrtomb.3, wcscasecmp.3, wcscat.3, wcschr.3, wcscmp.3, wcscpy.3, wcscspn.3, wcsdup.3, wcslen.3, wcsncasecmp.3, wcsncat.3, wcsncmp.3, wcsncpy.3, wcsnlen.3, wcsnrtombs.3, wcspbrk.3, wcsrchr.3, wcsrtombs.3, wcsspn.3, wcsstr.3, wcstoimax.3, wcstok.3, wcstombs.3, wcswidth.3, wctob.3, wctomb.3, wctrans.3, wctype.3, wcwidth.3, wmemchr.3, wmemcmp.3, wmemcpy.3, wmemmove.3, wmemset.3, wordexp.3, wprintf.3, xcrypt.3, xdr.3, y0.3, cciss.4, console.4, console_codes.4, console_ioctl.4, dsp56k.4, fd.4, full.4, hd.4, hpsa.4, initrd.4, intro.4, lp.4, mem.4, mouse.4, null.4, pts.4, ram.4, random.4, rtc.4, sk98lin.4, st.4, tty.4, ttyS.4, tty_ioctl.4, vcs.4, wavelan.4, acct.5, charmap.5, dir_colors.5, filesystems.5, ftpusers.5, group.5, host.conf.5, hosts.5, hosts.equiv.5, intro.5, issue.5, locale.5, motd.5, networks.5, nologin.5, nscd.conf.5, passwd.5, proc.5, protocols.5, resolv.conf.5, rpc.5, securetty.5, services.5, shells.5, termcap.5, ttytype.5, utmp.5, armscii-8.7, arp.7, ascii.7, bootparam.7, capabilities.7, charsets.7, complex.7, cp1251.7, credentials.7, ddp.7, environ.7, epoll.7, fifo.7, futex.7, glob.7, hier.7, icmp.7, inotify.7, intro.7, ip.7, ipv6.7, iso_8859-1.7, iso_8859-10.7, iso_8859-11.7, iso_8859-13.7, iso_8859-14.7, iso_8859-15.7, iso_8859-16.7, iso_8859-2.7, iso_8859-3.7, iso_8859-4.7, iso_8859-5.7, iso_8859-6.7, iso_8859-7.7, iso_8859-8.7, iso_8859-9.7, koi8-r.7, koi8-u.7, locale.7, mailaddr.7, man.7, mq_overview.7, netdevice.7, netlink.7, numa.7, packet.7, path_resolution.7, pipe.7, posixoptions.7, pthreads.7, pty.7, raw.7, regex.7, rtld-audit.7, rtnetlink.7, sem_overview.7, shm_overview.7, sigevent.7, signal.7, socket.7, standards.7, suffixes.7, svipc.7, tcp.7, termio.7, time.7, udp.7, udplite.7, unicode.7, unix.7, uri.7, utf-8.7, x25.7, nscd.8, sync.8, tzselect.8, zdump.8, zic.8: Global fix: remove unneeded double quotes in .SH headings
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-02-24 18:01:36 +00:00
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.SH NOTES
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2004-11-03 13:51:07 +00:00
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.PP
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2008-11-28 16:31:35 +00:00
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To reiterate, bare futexes are not intended as an easy-to-use abstraction
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2007-04-12 22:42:49 +00:00
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for end-users.
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2008-11-28 16:31:35 +00:00
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(There is no wrapper function for this system call in glibc.)
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2007-04-12 22:42:49 +00:00
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Implementors are expected to be assembly literate and to have
|
eventfd.2, futex.2, mmap2.2, open.2, pciconfig_read.2, ptrace.2, reboot.2, request_key.2, sched_rr_get_interval.2, splice.2, stat.2, sync_file_range.2, syscalls.2, timer_create.2, vm86.2, pthread_attr_setscope.3, core.5, proc.5, aio.7, futex.7, netlink.7, time.7: Global fix: "userspace" ==> "user space" or "user-space"
Existing pages variously use "userspace or "user space".
But, "userspace" is not quite an English word.
So change "userspace" to "user space" or, when used
attributively, "user-space".
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2012-10-21 06:04:42 +00:00
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read the sources of the futex user-space library referenced below.
|
iconv.1, localedef.1, access.2, execveat.2, fanotify_init.2, futex.2, ioctl_fat.2, mount.2, ftw.3, sd.4, tty_ioctl.4, fanotify.7, futex.7, posixoptions.7, iconvconfig.8: srcfix: Remove useless quotes from .SS and .SH sections
Signed-off-by: Stéphane Aulery <saulery@free.fr>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2015-03-08 02:03:52 +00:00
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.\" .SH AUTHORS
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2004-11-03 13:51:07 +00:00
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.\" .PP
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.\" Futexes were designed and worked on by
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.\" Hubertus Franke (IBM Thomas J. Watson Research Center),
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.\" Matthew Kirkwood, Ingo Molnar (Red Hat)
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.\" and Rusty Russell (IBM Linux Technology Center).
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.\" This page written by bert hubert.
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getent.1, intro.1, time.1, _exit.2, _syscall.2, accept.2, access.2, acct.2, adjtimex.2, alarm.2, alloc_hugepages.2, arch_prctl.2, bdflush.2, bind.2, brk.2, cacheflush.2, capget.2, chdir.2, chmod.2, chown.2, chroot.2, clock_getres.2, clock_nanosleep.2, clone.2, close.2, connect.2, create_module.2, delete_module.2, dup.2, epoll_create.2, epoll_ctl.2, epoll_wait.2, eventfd.2, execve.2, exit_group.2, faccessat.2, fchmodat.2, fchownat.2, fcntl.2, flock.2, fork.2, fstatat.2, fsync.2, futex.2, futimesat.2, get_kernel_syms.2, get_robust_list.2, get_thread_area.2, getcpu.2, getdents.2, getdomainname.2, getgid.2, getgroups.2, gethostname.2, getitimer.2, getpagesize.2, getpeername.2, getpid.2, getpriority.2, getresuid.2, getrlimit.2, getrusage.2, getsid.2, getsockname.2, getsockopt.2, gettid.2, gettimeofday.2, getuid.2, getunwind.2, getxattr.2, idle.2, init_module.2, inotify_add_watch.2, inotify_init.2, inotify_rm_watch.2, intro.2, io_cancel.2, io_destroy.2, io_getevents.2, io_setup.2, io_submit.2, ioctl.2, ioctl_list.2, ioperm.2, iopl.2, ioprio_set.2, ipc.2, kcmp.2, kill.2, killpg.2, link.2, linkat.2, listen.2, listxattr.2, llseek.2, lookup_dcookie.2, lseek.2, madvise.2, migrate_pages.2, mincore.2, mkdir.2, mkdirat.2, mknod.2, mknodat.2, mlock.2, mmap.2, mmap2.2, modify_ldt.2, mount.2, move_pages.2, mprotect.2, mq_getsetattr.2, mremap.2, msgctl.2, msgget.2, msgop.2, msync.2, nanosleep.2, nfsservctl.2, nice.2, open.2, openat.2, outb.2, pause.2, pciconfig_read.2, perf_event_open.2, perfmonctl.2, personality.2, pipe.2, pivot_root.2, poll.2, posix_fadvise.2, prctl.2, pread.2, process_vm_readv.2, ptrace.2, query_module.2, quotactl.2, read.2, readahead.2, readdir.2, readlink.2, readlinkat.2, readv.2, reboot.2, recv.2, remap_file_pages.2, removexattr.2, rename.2, renameat.2, rmdir.2, rt_sigqueueinfo.2, sched_get_priority_max.2, sched_rr_get_interval.2, sched_setaffinity.2, sched_setparam.2, sched_setscheduler.2, sched_yield.2, select.2, semctl.2, semget.2, semop.2, send.2, sendfile.2, set_thread_area.2, set_tid_address.2, seteuid.2, setfsgid.2, setfsuid.2, setgid.2, setpgid.2, setresuid.2, setreuid.2, setsid.2, setuid.2, setup.2, setxattr.2, shmctl.2, shmget.2, shmop.2, shutdown.2, sigaction.2, sigaltstack.2, signal.2, signalfd.2, sigpending.2, sigprocmask.2, sigreturn.2, sigsuspend.2, sigwaitinfo.2, socket.2, socketcall.2, socketpair.2, splice.2, stat.2, statfs.2, stime.2, swapon.2, symlink.2, symlinkat.2, sync.2, sync_file_range.2, sysctl.2, sysfs.2, sysinfo.2, syslog.2, tee.2, time.2, timerfd_create.2, times.2, tkill.2, truncate.2, umask.2, umount.2, uname.2, unimplemented.2, unlink.2, unlinkat.2, uselib.2, ustat.2, utime.2, utimensat.2, vfork.2, vhangup.2, vm86.2, vmsplice.2, wait.2, wait4.2, write.2, CPU_SET.3, INFINITY.3, MB_CUR_MAX.3, MB_LEN_MAX.3, __setfpucw.3, a64l.3, abort.3, abs.3, acos.3, acosh.3, addseverity.3, adjtime.3, aio_cancel.3, aio_error.3, aio_fsync.3, aio_read.3, aio_return.3, aio_suspend.3, aio_write.3, alloca.3, argz_add.3, asin.3, asinh.3, asprintf.3, assert.3, assert_perror.3, atan.3, atan2.3, atanh.3, atexit.3, atof.3, atoi.3, backtrace.3, basename.3, bcmp.3, bcopy.3, bindresvport.3, bsd_signal.3, bsearch.3, bstring.3, btowc.3, btree.3, byteorder.3, bzero.3, cabs.3, cacos.3, cacosh.3, canonicalize_file_name.3, carg.3, casin.3, casinh.3, catan.3, catanh.3, catgets.3, catopen.3, cbrt.3, ccos.3, ccosh.3, ceil.3, cerf.3, cexp.3, cexp2.3, cfree.3, cimag.3, clearenv.3, clock.3, clock_getcpuclockid.3, clog.3, clog10.3, clog2.3, closedir.3, cmsg.3, confstr.3, conj.3, copysign.3, cos.3, cosh.3, cpow.3, cproj.3, creal.3, crypt.3, csin.3, csinh.3, csqrt.3, ctan.3, ctanh.3, ctermid.3, ctime.3, daemon.3, dbopen.3, des_crypt.3, difftime.3, dirfd.3, div.3, dl_iterate_phdr.3, dlopen.3, dprintf.3, drand48.3, drand48_r.3, dysize.3, ecvt.3, ecvt_r.3, encrypt.3, end.3, endian.3, envz_add.3, erf.3, erfc.3, err.3, errno.3, error.3, ether_aton.3, euidaccess.3, exec.3, exit.3, exp.3, exp10.3, exp2.3, expm1.3, fabs.3, fclose.3, fcloseall.3, fdim.3, fenv.3, ferror.3, fexecve.3, fflush.3, ffs.3, fgetgrent.3, fgetpwent.3, fgetwc.3, fgetws.3, finite.3, flockfile.3, floor.3, fma.3, fmax.3, fmemopen.3, fmin.3, fmod.3, fmtmsg.3, fnmatch.3, fopen.3, fpathconf.3, fpclassify.3, fpurge.3, fputwc.3, fputws.3, fread.3, frexp.3, fseek.3, fseeko.3, ftime.3, ftok.3, fts.3, ftw.3, futimes.3, fwide.3, gamma.3, gcvt.3, getaddrinfo.3, getaddrinfo_a.3, getauxval.3, getcontext.3, getcwd.3, getdate.3, getdirentries.3, getdtablesize.3, getenv.3, getfsent.3, getgrent.3, getgrent_r.3, getgrnam.3, getgrouplist.3, gethostbyname.3, gethostid.3, getipnodebyname.3, getline.3, getloadavg.3, getlogin.3, getmntent.3, getnameinfo.3, getnetent.3, getnetent_r.3, getopt.3, getpass.3, getprotoent.3, getprotoent_r.3, getpt.3, getpw.3, getpwent.3, getpwent_r.3, getpwnam.3, getrpcent.3, getrpcent_r.3, getrpcport.3, gets.3, getservent.3, getservent_r.3, getspnam.3, getttyent.3, getumask.3, getusershell.3, getutent.3, getw.3, getwchar.3, glob.3, grantpt.3, gsignal.3, hash.3, hsearch.3, hypot.3, iconv.3, iconv_close.3, iconv_open.3, ilogb.3, index.3, inet.3, inet_ntop.3, inet_pton.3, infnan.3, initgroups.3, insque.3, intro.3, isalpha.3, isatty.3, isgreater.3, iswalnum.3, iswalpha.3, iswblank.3, iswcntrl.3, iswctype.3, iswdigit.3, iswgraph.3, iswlower.3, iswprint.3, iswpunct.3, iswspace.3, iswupper.3, iswxdigit.3, j0.3, key_setsecret.3, ldexp.3, lgamma.3, lio_listio.3, localeconv.3, lockf.3, log.3, log10.3, log1p.3, log2.3, logb.3, login.3, longjmp.3, lrint.3, lround.3, lsearch.3, lseek64.3, makecontext.3, makedev.3, malloc.3, malloc_hook.3, mblen.3, mbrlen.3, mbrtowc.3, mbsinit.3, mbsnrtowcs.3, mbsrtowcs.3, mbstowcs.3, mbtowc.3, memccpy.3, memchr.3, memcmp.3, memcpy.3, memfrob.3, memmem.3, memmove.3, mempcpy.3, memset.3, mkdtemp.3, mkfifo.3, mkfifoat.3, mkstemp.3, mktemp.3, modf.3, mpool.3, mq_close.3, mq_getattr.3, mq_notify.3, mq_open.3, mq_receive.3, mq_send.3, mq_unlink.3, mtrace.3, nan.3, netlink.3, nextafter.3, nl_langinfo.3, offsetof.3, on_exit.3, opendir.3, openpty.3, perror.3, popen.3, posix_fallocate.3, posix_memalign.3, posix_openpt.3, pow.3, pow10.3, printf.3, profil.3, program_invocation_name.3, psignal.3, pthread_kill_other_threads_np.3, ptsname.3, putenv.3, putgrent.3, putpwent.3, puts.3, putwchar.3, qecvt.3, qsort.3, queue.3, raise.3, rand.3, random.3, random_r.3, rcmd.3, re_comp.3, readdir.3, realpath.3, recno.3, regex.3, remainder.3, remove.3, remquo.3, resolver.3, rewinddir.3, rexec.3, rint.3, round.3, rpc.3, rpmatch.3, rtime.3, rtnetlink.3, scalb.3, scalbln.3, scandir.3, scandirat.3, scanf.3, seekdir.3, sem_close.3, sem_destroy.3, sem_getvalue.3, sem_init.3, sem_open.3, sem_post.3, sem_unlink.3, sem_wait.3, setaliasent.3, setbuf.3, setenv.3, setjmp.3, setlocale.3, setlogmask.3, setnetgrent.3, shm_open.3, siginterrupt.3, signbit.3, significand.3, sigpause.3, sigqueue.3, sigset.3, sigsetops.3, sigvec.3, sin.3, sincos.3, sinh.3, sleep.3, sockatmark.3, sqrt.3, statvfs.3, stdarg.3, stdin.3, stdio.3, stdio_ext.3, stpcpy.3, stpncpy.3, strcasecmp.3, strcat.3, strchr.3, strcmp.3, strcoll.3, strcpy.3, strdup.3, strerror.3, strfmon.3, strfry.3, strftime.3, string.3, strlen.3, strnlen.3, strpbrk.3, strptime.3, strsep.3, strsignal.3, strspn.3, strstr.3, strtod.3, strtoimax.3, strtok.3, strtol.3, strtoul.3, strverscmp.3, strxfrm.3, swab.3, sysconf.3, syslog.3, system.3, sysv_signal.3, tan.3, tanh.3, tcgetpgrp.3, tcgetsid.3, telldir.3, tempnam.3, termios.3, tgamma.3, timegm.3, timeradd.3, tmpfile.3, tmpnam.3, toascii.3, toupper.3, towctrans.3, towlower.3, towupper.3, trunc.3, tsearch.3, ttyname.3, ttyslot.3, tzset.3, ualarm.3, ulimit.3, ungetwc.3, unlocked_stdio.3, unlockpt.3, updwtmp.3, usleep.3, wcpcpy.3, wcpncpy.3, wcrtomb.3, wcscasecmp.3, wcscat.3, wcschr.3, wcscmp.3, wcscpy.3, wcscspn.3, wcsdup.3, wcslen.3, wcsncasecmp.3, wcsncat.3, wcsncmp.3, wcsncpy.3, wcsnlen.3, wcsnrtombs.3, wcspbrk.3, wcsrchr.3, wcsrtombs.3, wcsspn.3, wcsstr.3, wcstoimax.3, wcstok.3, wcstombs.3, wcswidth.3, wctob.3, wctomb.3, wctrans.3, wctype.3, wcwidth.3, wmemchr.3, wmemcmp.3, wmemcpy.3, wmemmove.3, wmemset.3, wordexp.3, wprintf.3, xcrypt.3, xdr.3, y0.3, cciss.4, console.4, console_codes.4, console_ioctl.4, dsp56k.4, fd.4, full.4, hd.4, hpsa.4, initrd.4, intro.4, lp.4, mem.4, mouse.4, null.4, pts.4, ram.4, random.4, rtc.4, sk98lin.4, st.4, tty.4, ttyS.4, tty_ioctl.4, vcs.4, wavelan.4, acct.5, charmap.5, dir_colors.5, filesystems.5, ftpusers.5, group.5, host.conf.5, hosts.5, hosts.equiv.5, intro.5, issue.5, locale.5, motd.5, networks.5, nologin.5, nscd.conf.5, passwd.5, proc.5, protocols.5, resolv.conf.5, rpc.5, securetty.5, services.5, shells.5, termcap.5, ttytype.5, utmp.5, armscii-8.7, arp.7, ascii.7, bootparam.7, capabilities.7, charsets.7, complex.7, cp1251.7, credentials.7, ddp.7, environ.7, epoll.7, fifo.7, futex.7, glob.7, hier.7, icmp.7, inotify.7, intro.7, ip.7, ipv6.7, iso_8859-1.7, iso_8859-10.7, iso_8859-11.7, iso_8859-13.7, iso_8859-14.7, iso_8859-15.7, iso_8859-16.7, iso_8859-2.7, iso_8859-3.7, iso_8859-4.7, iso_8859-5.7, iso_8859-6.7, iso_8859-7.7, iso_8859-8.7, iso_8859-9.7, koi8-r.7, koi8-u.7, locale.7, mailaddr.7, man.7, mq_overview.7, netdevice.7, netlink.7, numa.7, packet.7, path_resolution.7, pipe.7, posixoptions.7, pthreads.7, pty.7, raw.7, regex.7, rtld-audit.7, rtnetlink.7, sem_overview.7, shm_overview.7, sigevent.7, signal.7, socket.7, standards.7, suffixes.7, svipc.7, tcp.7, termio.7, time.7, udp.7, udplite.7, unicode.7, unix.7, uri.7, utf-8.7, x25.7, nscd.8, sync.8, tzselect.8, zdump.8, zic.8: Global fix: remove unneeded double quotes in .SH headings
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-02-24 18:01:36 +00:00
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.SH SEE ALSO
|
2015-01-13 16:03:14 +00:00
|
|
|
.BR get_robust_list (2),
|
2013-07-30 03:09:22 +00:00
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.BR restart_syscall (2),
|
2007-12-17 11:28:40 +00:00
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|
.BR futex (7)
|
2004-11-03 13:51:07 +00:00
|
|
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.PP
|
2007-06-21 21:58:51 +00:00
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\fIFuss, Futexes and Furwocks: Fast Userlevel Locking in Linux\fP
|
2010-05-22 03:23:14 +00:00
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(proceedings of the Ottawa Linux Symposium 2002), online at
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.br
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capget.2, futex.2, sched_setscheduler.2, spu_create.2, spu_run.2, vfork.2, getnameinfo.3, netlink.3, cciss.4, console_codes.4, dsp56k.4, hpsa.4, sk98lin.4, filesystems.5, protocols.5, aio.7, capabilities.7, charsets.7, feature_test_macros.7, futex.7, hier.7, iso_8859-16.7, iso_8859-2.7, koi8-r.7, libc.7, man.7, netlink.7, numa.7, standards.7, unicode.7, units.7, uri.7, x25.7: Global fix: use UR macro where applicable
The syntax .UR http://example.com paired with .UE will create
links which one can interact, if the pager allows that. One
way to see the effect is ask the man(1) command to use browser
display, e.g.:
man -H man7/uri.7
("\:" is optional groff syntax to permit hyphenless line breaks.)
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2012-08-13 08:02:36 +00:00
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.UR http://kernel.org\:/doc\:/ols\:/2002\:/ols2002-pages-479-495.pdf
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.UE
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2015-01-12 16:00:14 +00:00
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\fIFutexes Are Tricky\fP (updated in 2011), Ulrich Drepper
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.UR http://www.akkadia.org/drepper/futex.pdf
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.UE
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2010-05-22 03:23:14 +00:00
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.PP
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Futex example library, futex-*.tar.bz2 at
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.br
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2013-09-30 18:50:43 +00:00
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.UR ftp://ftp.kernel.org\:/pub\:/linux\:/kernel\:/people\:/rusty/
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capget.2, futex.2, sched_setscheduler.2, spu_create.2, spu_run.2, vfork.2, getnameinfo.3, netlink.3, cciss.4, console_codes.4, dsp56k.4, hpsa.4, sk98lin.4, filesystems.5, protocols.5, aio.7, capabilities.7, charsets.7, feature_test_macros.7, futex.7, hier.7, iso_8859-16.7, iso_8859-2.7, koi8-r.7, libc.7, man.7, netlink.7, numa.7, standards.7, unicode.7, units.7, uri.7, x25.7: Global fix: use UR macro where applicable
The syntax .UR http://example.com paired with .UE will create
links which one can interact, if the pager allows that. One
way to see the effect is ask the man(1) command to use browser
display, e.g.:
man -H man7/uri.7
("\:" is optional groff syntax to permit hyphenless line breaks.)
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2012-08-13 08:02:36 +00:00
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.UE
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