2004-11-03 13:51:07 +00:00
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.\" Copyright (c) 1992 Drew Eckhardt (drew@cs.colorado.edu), March 28, 1992
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2007-09-20 06:52:22 +00:00
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.\" and Copyright (c) 2006 Michael Kerrisk <mtk.manpages@gmail.com>
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2004-11-03 13:51:07 +00:00
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.\"
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intro.1, _exit.2, access.2, alarm.2, alloc_hugepages.2, arch_prctl.2, bind.2, chdir.2, chmod.2, chown.2, chroot.2, clock_getres.2, clock_nanosleep.2, close.2, connect.2, delete_module.2, dup.2, execve.2, exit_group.2, faccessat.2, fchmodat.2, fchownat.2, fcntl.2, fork.2, fstatat.2, fsync.2, futimesat.2, get_robust_list.2, getdents.2, getdomainname.2, getgid.2, getgroups.2, gethostname.2, getpagesize.2, getpid.2, getresuid.2, getrlimit.2, getrusage.2, gettid.2, gettimeofday.2, getuid.2, getunwind.2, idle.2, init_module.2, intro.2, iopl.2, kcmp.2, kexec_load.2, kill.2, link.2, linkat.2, llseek.2, lookup_dcookie.2, madvise.2, mincore.2, mkdirat.2, mknodat.2, mmap.2, mmap2.2, mount.2, mprotect.2, mq_getsetattr.2, msgctl.2, msgget.2, msgop.2, msync.2, nice.2, open.2, openat.2, pause.2, perfmonctl.2, personality.2, pipe.2, poll.2, posix_fadvise.2, prctl.2, pread.2, process_vm_readv.2, quotactl.2, read.2, readahead.2, readdir.2, readlinkat.2, readv.2, reboot.2, recvmmsg.2, remap_file_pages.2, rename.2, renameat.2, rmdir.2, rt_sigqueueinfo.2, select.2, select_tut.2, semctl.2, semget.2, semop.2, sendmmsg.2, set_tid_address.2, seteuid.2, setfsgid.2, setfsuid.2, setgid.2, setresuid.2, setuid.2, setup.2, sgetmask.2, shmctl.2, shmget.2, shmop.2, sigaction.2, sigaltstack.2, signal.2, sigpending.2, sigprocmask.2, sigreturn.2, sigsuspend.2, sigwaitinfo.2, splice.2, stat.2, statfs.2, stime.2, subpage_prot.2, swapon.2, symlink.2, symlinkat.2, sync.2, sync_file_range.2, syscalls.2, sysctl.2, sysfs.2, syslog.2, tee.2, time.2, timer_create.2, timer_delete.2, timer_getoverrun.2, timer_settime.2, times.2, tkill.2, umask.2, umount.2, uname.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, abort.3, abs.3, acos.3, acosh.3, adjtime.3, aio_init.3, asin.3, asinh.3, asprintf.3, assert.3, assert_perror.3, atan.3, atan2.3, atanh.3, atexit.3, atof.3, atoi.3, basename.3, bcmp.3, bcopy.3, bindresvport.3, bsd_signal.3, bsearch.3, bstring.3, byteorder.3, bzero.3, catgets.3, catopen.3, cbrt.3, ceil.3, clearenv.3, clock.3, clock_getcpuclockid.3, closedir.3, confstr.3, copysign.3, cos.3, cosh.3, ctermid.3, ctime.3, difftime.3, dirfd.3, div.3, dl_iterate_phdr.3, dprintf.3, drand48.3, drand48_r.3, dysize.3, ecvt.3, ecvt_r.3, end.3, endian.3, erf.3, erfc.3, ether_aton.3, euidaccess.3, exit.3, exp.3, exp10.3, exp2.3, expm1.3, fabs.3, fcloseall.3, fexecve.3, ffs.3, fgetgrent.3, fgetpwent.3, finite.3, flockfile.3, floor.3, fmod.3, fnmatch.3, fopencookie.3, fpathconf.3, fpurge.3, frexp.3, fseeko.3, ftok.3, futimes.3, gcvt.3, get_nprocs_conf.3, getaddrinfo.3, getaddrinfo_a.3, getauxval.3, getcontext.3, getcwd.3, getdate.3, getdirentries.3, getdtablesize.3, getenv.3, getfsent.3, getgrent.3, getgrnam.3, getgrouplist.3, gethostbyname.3, gethostid.3, getifaddrs.3, getipnodebyname.3, getline.3, getlogin.3, getmntent.3, getnetent.3, getnetent_r.3, getopt.3, getprotoent.3, getprotoent_r.3, getpw.3, getpwent.3, getpwnam.3, getrpcent_r.3, gets.3, getservent.3, getservent_r.3, getumask.3, getusershell.3, getutmp.3, getw.3, glob.3, gnu_get_libc_version.3, gsignal.3, hypot.3, if_nameindex.3, if_nametoindex.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, j0.3, ldexp.3, localeconv.3, log.3, log10.3, log1p.3, log2.3, logb.3, lrint.3, lround.3, lsearch.3, lseek64.3, makecontext.3, makedev.3, mallinfo.3, malloc.3, malloc_get_state.3, malloc_info.3, malloc_stats.3, malloc_trim.3, malloc_usable_size.3, mallopt.3, matherr.3, mcheck.3, memccpy.3, memchr.3, memcmp.3, memcpy.3, memfrob.3, memmem.3, memmove.3, memset.3, mkdtemp.3, mkfifo.3, mkfifoat.3, mkstemp.3, mktemp.3, modf.3, mq_close.3, mq_getattr.3, mq_notify.3, mq_open.3, mq_receive.3, mq_send.3, mq_unlink.3, mtrace.3, on_exit.3, opendir.3, posix_fallocate.3, posix_memalign.3, posix_openpt.3, pow.3, pow10.3, profil.3, psignal.3, pthread_attr_init.3, pthread_attr_setaffinity_np.3, pthread_attr_setdetachstate.3, pthread_attr_setguardsize.3, pthread_attr_setinheritsched.3, pthread_attr_setschedparam.3, pthread_attr_setschedpolicy.3, pthread_attr_setscope.3, pthread_attr_setstack.3, pthread_attr_setstackaddr.3, pthread_attr_setstacksize.3, pthread_cancel.3, pthread_cleanup_push.3, pthread_cleanup_push_defer_np.3, pthread_create.3, pthread_detach.3, pthread_equal.3, pthread_exit.3, pthread_getattr_np.3, pthread_getcpuclockid.3, pthread_join.3, pthread_kill.3, pthread_kill_other_threads_np.3, pthread_self.3, pthread_setaffinity_np.3, pthread_setcancelstate.3, pthread_setconcurrency.3, pthread_setname_np.3, pthread_setschedparam.3, pthread_setschedprio.3, pthread_sigmask.3, pthread_sigqueue.3, pthread_testcancel.3, pthread_tryjoin_np.3, pthread_yield.3, putenv.3, putpwent.3, puts.3, qecvt.3, qsort.3, raise.3, rand.3, random.3, random_r.3, re_comp.3, readdir.3, realpath.3, regex.3, remainder.3, remove.3, resolver.3, rewinddir.3, rint.3, round.3, scalb.3, scalbln.3, scandir.3, sched_getcpu.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, setenv.3, setlocale.3, setlogmask.3, shm_open.3, siginterrupt.3, sigpause.3, sigqueue.3, sigset.3, sigsetops.3, sigvec.3, sigwait.3, sin.3, sinh.3, sleep.3, sockatmark.3, sqrt.3, statvfs.3, stdio_ext.3, stpcpy.3, strcasecmp.3, strcat.3, strchr.3, strcmp.3, strcoll.3, strcpy.3, strdup.3, strerror.3, strfry.3, strftime.3, string.3, strlen.3, strpbrk.3, strptime.3, strsep.3, strsignal.3, strspn.3, strstr.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, timegm.3, timeradd.3, tmpfile.3, tmpnam.3, toascii.3, toupper.3, trunc.3, tsearch.3, ttyslot.3, tzset.3, ulimit.3, undocumented.3, unlocked_stdio.3, usleep.3, y0.3, cpuid.4, full.4, initrd.4, mouse.4, msr.4, sd.4, st.4, acct.5, core.5, services.5, slabinfo.5, aio.7, capabilities.7, credentials.7, feature_test_macros.7, hier.7, inotify.7, libc.7, locale.7, man-pages.7, man.7, math_error.7, mq_overview.7, numa.7, path_resolution.7, pipe.7, pthreads.7, pty.7, rtld-audit.7, sem_overview.7, shm_overview.7, sigevent.7, signal.7, suffixes.7, svipc.7, termio.7, time.7, udplite.7, units.7, uri.7, sln.8: s/LICENSE_START(verbatim)/LICENSE_START(VERBATIM)/
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-03-10 09:29:01 +00:00
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.\" %%%LICENSE_START(VERBATIM)
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2004-11-03 13:51:07 +00:00
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.\" Permission is granted to make and distribute verbatim copies of this
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.\" manual provided the copyright notice and this permission notice are
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.\" preserved on all copies.
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.\"
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.\" Permission is granted to copy and distribute modified versions of this
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.\" manual under the conditions for verbatim copying, provided that the
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.\" entire resulting derived work is distributed under the terms of a
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.\" permission notice identical to this one.
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2007-04-12 22:42:49 +00:00
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.\"
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2004-11-03 13:51:07 +00:00
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.\" Since the Linux kernel and libraries are constantly changing, this
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.\" manual page may be incorrect or out-of-date. The author(s) assume no
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.\" responsibility for errors or omissions, or for damages resulting from
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.\" the use of the information contained herein. The author(s) may not
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.\" have taken the same level of care in the production of this manual,
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.\" which is licensed free of charge, as they might when working
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.\" professionally.
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2007-04-12 22:42:49 +00:00
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.\"
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2004-11-03 13:51:07 +00:00
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.\" Formatted or processed versions of this manual, if unaccompanied by
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.\" the source, must acknowledge the copyright and authors of this work.
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intro.1, _exit.2, access.2, alarm.2, alloc_hugepages.2, arch_prctl.2, bind.2, chdir.2, chmod.2, chown.2, chroot.2, clock_getres.2, clock_nanosleep.2, close.2, connect.2, delete_module.2, dup.2, execve.2, exit_group.2, faccessat.2, fchmodat.2, fchownat.2, fcntl.2, fork.2, fstatat.2, fsync.2, futimesat.2, get_robust_list.2, getdents.2, getdomainname.2, getgid.2, getgroups.2, gethostname.2, getpagesize.2, getpid.2, getresuid.2, getrlimit.2, getrusage.2, gettid.2, gettimeofday.2, getuid.2, getunwind.2, idle.2, init_module.2, intro.2, iopl.2, kcmp.2, kexec_load.2, kill.2, link.2, linkat.2, llseek.2, lookup_dcookie.2, madvise.2, mincore.2, mkdirat.2, mknodat.2, mmap.2, mmap2.2, mount.2, mprotect.2, mq_getsetattr.2, msgctl.2, msgget.2, msgop.2, msync.2, nice.2, open.2, openat.2, pause.2, perfmonctl.2, personality.2, pipe.2, poll.2, posix_fadvise.2, prctl.2, pread.2, process_vm_readv.2, quotactl.2, read.2, readahead.2, readdir.2, readlinkat.2, readv.2, reboot.2, recvmmsg.2, remap_file_pages.2, rename.2, renameat.2, rmdir.2, rt_sigqueueinfo.2, select.2, select_tut.2, semctl.2, semget.2, semop.2, sendmmsg.2, set_tid_address.2, seteuid.2, setfsgid.2, setfsuid.2, setgid.2, setresuid.2, setuid.2, setup.2, sgetmask.2, shmctl.2, shmget.2, shmop.2, sigaction.2, sigaltstack.2, signal.2, sigpending.2, sigprocmask.2, sigreturn.2, sigsuspend.2, sigwaitinfo.2, splice.2, stat.2, statfs.2, stime.2, subpage_prot.2, swapon.2, symlink.2, symlinkat.2, sync.2, sync_file_range.2, syscalls.2, sysctl.2, sysfs.2, syslog.2, tee.2, time.2, timer_create.2, timer_delete.2, timer_getoverrun.2, timer_settime.2, times.2, tkill.2, umask.2, umount.2, uname.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, abort.3, abs.3, acos.3, acosh.3, adjtime.3, aio_init.3, asin.3, asinh.3, asprintf.3, assert.3, assert_perror.3, atan.3, atan2.3, atanh.3, atexit.3, atof.3, atoi.3, basename.3, bcmp.3, bcopy.3, bindresvport.3, bsd_signal.3, bsearch.3, bstring.3, byteorder.3, bzero.3, catgets.3, catopen.3, cbrt.3, ceil.3, clearenv.3, clock.3, clock_getcpuclockid.3, closedir.3, confstr.3, copysign.3, cos.3, cosh.3, ctermid.3, ctime.3, difftime.3, dirfd.3, div.3, dl_iterate_phdr.3, dprintf.3, drand48.3, drand48_r.3, dysize.3, ecvt.3, ecvt_r.3, end.3, endian.3, erf.3, erfc.3, ether_aton.3, euidaccess.3, exit.3, exp.3, exp10.3, exp2.3, expm1.3, fabs.3, fcloseall.3, fexecve.3, ffs.3, fgetgrent.3, fgetpwent.3, finite.3, flockfile.3, floor.3, fmod.3, fnmatch.3, fopencookie.3, fpathconf.3, fpurge.3, frexp.3, fseeko.3, ftok.3, futimes.3, gcvt.3, get_nprocs_conf.3, getaddrinfo.3, getaddrinfo_a.3, getauxval.3, getcontext.3, getcwd.3, getdate.3, getdirentries.3, getdtablesize.3, getenv.3, getfsent.3, getgrent.3, getgrnam.3, getgrouplist.3, gethostbyname.3, gethostid.3, getifaddrs.3, getipnodebyname.3, getline.3, getlogin.3, getmntent.3, getnetent.3, getnetent_r.3, getopt.3, getprotoent.3, getprotoent_r.3, getpw.3, getpwent.3, getpwnam.3, getrpcent_r.3, gets.3, getservent.3, getservent_r.3, getumask.3, getusershell.3, getutmp.3, getw.3, glob.3, gnu_get_libc_version.3, gsignal.3, hypot.3, if_nameindex.3, if_nametoindex.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, j0.3, ldexp.3, localeconv.3, log.3, log10.3, log1p.3, log2.3, logb.3, lrint.3, lround.3, lsearch.3, lseek64.3, makecontext.3, makedev.3, mallinfo.3, malloc.3, malloc_get_state.3, malloc_info.3, malloc_stats.3, malloc_trim.3, malloc_usable_size.3, mallopt.3, matherr.3, mcheck.3, memccpy.3, memchr.3, memcmp.3, memcpy.3, memfrob.3, memmem.3, memmove.3, memset.3, mkdtemp.3, mkfifo.3, mkfifoat.3, mkstemp.3, mktemp.3, modf.3, mq_close.3, mq_getattr.3, mq_notify.3, mq_open.3, mq_receive.3, mq_send.3, mq_unlink.3, mtrace.3, on_exit.3, opendir.3, posix_fallocate.3, posix_memalign.3, posix_openpt.3, pow.3, pow10.3, profil.3, psignal.3, pthread_attr_init.3, pthread_attr_setaffinity_np.3, pthread_attr_setdetachstate.3, pthread_attr_setguardsize.3, pthread_attr_setinheritsched.3, pthread_attr_setschedparam.3, pthread_attr_setschedpolicy.3, pthread_attr_setscope.3, pthread_attr_setstack.3, pthread_attr_setstackaddr.3, pthread_attr_setstacksize.3, pthread_cancel.3, pthread_cleanup_push.3, pthread_cleanup_push_defer_np.3, pthread_create.3, pthread_detach.3, pthread_equal.3, pthread_exit.3, pthread_getattr_np.3, pthread_getcpuclockid.3, pthread_join.3, pthread_kill.3, pthread_kill_other_threads_np.3, pthread_self.3, pthread_setaffinity_np.3, pthread_setcancelstate.3, pthread_setconcurrency.3, pthread_setname_np.3, pthread_setschedparam.3, pthread_setschedprio.3, pthread_sigmask.3, pthread_sigqueue.3, pthread_testcancel.3, pthread_tryjoin_np.3, pthread_yield.3, putenv.3, putpwent.3, puts.3, qecvt.3, qsort.3, raise.3, rand.3, random.3, random_r.3, re_comp.3, readdir.3, realpath.3, regex.3, remainder.3, remove.3, resolver.3, rewinddir.3, rint.3, round.3, scalb.3, scalbln.3, scandir.3, sched_getcpu.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, setenv.3, setlocale.3, setlogmask.3, shm_open.3, siginterrupt.3, sigpause.3, sigqueue.3, sigset.3, sigsetops.3, sigvec.3, sigwait.3, sin.3, sinh.3, sleep.3, sockatmark.3, sqrt.3, statvfs.3, stdio_ext.3, stpcpy.3, strcasecmp.3, strcat.3, strchr.3, strcmp.3, strcoll.3, strcpy.3, strdup.3, strerror.3, strfry.3, strftime.3, string.3, strlen.3, strpbrk.3, strptime.3, strsep.3, strsignal.3, strspn.3, strstr.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, timegm.3, timeradd.3, tmpfile.3, tmpnam.3, toascii.3, toupper.3, trunc.3, tsearch.3, ttyslot.3, tzset.3, ulimit.3, undocumented.3, unlocked_stdio.3, usleep.3, y0.3, cpuid.4, full.4, initrd.4, mouse.4, msr.4, sd.4, st.4, acct.5, core.5, services.5, slabinfo.5, aio.7, capabilities.7, credentials.7, feature_test_macros.7, hier.7, inotify.7, libc.7, locale.7, man-pages.7, man.7, math_error.7, mq_overview.7, numa.7, path_resolution.7, pipe.7, pthreads.7, pty.7, rtld-audit.7, sem_overview.7, shm_overview.7, sigevent.7, signal.7, suffixes.7, svipc.7, termio.7, time.7, udplite.7, units.7, uri.7, sln.8: Global fix: Add LICENSE_START(verbatim)
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-03-10 09:28:40 +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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.\" Modified by Michael Haardt <michael@moria.de>
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.\" Modified 1993-07-21 by Rik Faith <faith@cs.unc.edu>
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.\" Modified 1994-08-21 by Michael Chastain <mec@shell.portal.com>:
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.\" Modified 1997-01-31 by Eric S. Raymond <esr@thyrsus.com>
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.\" Modified 1999-11-12 by Urs Thuermann <urs@isnogud.escape.de>
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2007-09-20 06:52:22 +00:00
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.\" Modified 2004-06-23 by Michael Kerrisk <mtk.manpages@gmail.com>
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.\" 2006-09-04 Michael Kerrisk <mtk.manpages@gmail.com>
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2007-04-30 12:25:52 +00:00
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.\" Added list of process attributes that are not preserved on exec().
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2007-09-10 04:31:59 +00:00
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.\" 2007-09-14 Ollie Wild <aaw@google.com>, mtk
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.\" Add text describing limits on command-line arguments + environment
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2004-11-03 13:51:07 +00:00
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.\"
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add_key.2, chown.2, epoll_ctl.2, epoll_wait.2, execve.2, fcntl.2, get_mempolicy.2, getxattr.2, ioctl.2, keyctl.2, listxattr.2, mkdir.2, mknod.2, mmap.2, msync.2, nfsservctl.2, open.2, prctl.2, removexattr.2, request_key.2, sendfile.2, set_mempolicy.2, setxattr.2, shmget.2, shutdown.2, sigaction.2, syslog.2, truncate.2, umask.2, CPU_SET.3, atexit.3, bsearch.3, cmsg.3, err.3, gethostid.3, getmntent.3, getopt.3, iconv_close.3, inet_ntop.3, longjmp.3, lsearch.3, mcheck.3, on_exit.3, putpwent.3, regex.3, resolver.3, setbuf.3, setjmp.3, setlocale.3, setlogmask.3, sleep.3, strsignal.3, sysconf.3, undocumented.3, tty_ioctl.4, proc.5, resolv.conf.5, tzfile.5, aio.7, bootparam.7, capabilities.7, fanotify.7, inotify.7, ip.7, packet.7, pthreads.7, raw.7, signal.7, socket.7, unix.7, ld.so.8, nscd.8: tstamp
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2015-05-07 06:26:32 +00:00
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.TH EXECVE 2 2015-05-07 "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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execve \- execute program
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.SH SYNOPSIS
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.B #include <unistd.h>
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.sp
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2006-03-06 04:40:24 +00:00
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.BI "int execve(const char *" filename ", char *const " argv "[], "
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.br
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.BI " char *const " envp []);
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2004-11-03 13:51:07 +00:00
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.SH DESCRIPTION
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2007-05-12 09:06:04 +00:00
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.BR execve ()
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executes the program pointed to by \fIfilename\fP.
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2004-11-03 13:51:07 +00:00
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\fIfilename\fP must be either a binary executable, or a script
|
2007-04-30 09:00:59 +00:00
|
|
|
starting with a line of the form:
|
|
|
|
|
2007-12-19 06:57:44 +00:00
|
|
|
.in +4n
|
2007-04-30 09:00:59 +00:00
|
|
|
.nf
|
2007-07-18 20:24:30 +00:00
|
|
|
\fB#!\fP \fIinterpreter \fP[optional-arg]
|
2007-04-30 09:00:59 +00:00
|
|
|
.fi
|
|
|
|
.in
|
|
|
|
|
2007-04-30 12:25:52 +00:00
|
|
|
For details of the latter case, see "Interpreter scripts" below.
|
2004-11-03 13:51:07 +00:00
|
|
|
|
|
|
|
\fIargv\fP is an array of argument strings passed to the new program.
|
2011-09-14 05:57:12 +00:00
|
|
|
By convention, the first of these strings should contain the filename
|
|
|
|
associated with the file being executed.
|
2004-11-03 13:51:07 +00:00
|
|
|
\fIenvp\fP is an array of strings, conventionally of the form
|
2007-07-18 20:24:30 +00:00
|
|
|
\fBkey=value\fP, which are passed as environment to the new program.
|
epoll_ctl.2, execve.2, recv.2, timer_create.2, wait.2, argz_add.3, basename.3, dlopen.3, exec.3, fopencookie.3, fts.3, getaddrinfo.3, getcwd.3, gethostbyname.3, getifaddrs.3, getipnodebyname.3, getlogin.3, getnetent.3, getprotoent.3, getrpcent.3, getservent.3, getusershell.3, glob.3, if_nameindex.3, inet_ntop.3, lio_listio.3, mblen.3, mbrlen.3, mbrtowc.3, mbsinit.3, mbsnrtowcs.3, mbsrtowcs.3, mbstowcs.3, mq_notify.3, ptsname.3, realpath.3, setnetgrent.3, sigvec.3, strsignal.3, strtok.3, wcrtomb.3, wcsnrtombs.3, wcsrtombs.3, wcstombs.3, xdr.3: Global fix of "NULL pointer"
Change "NULL pointer: to "NUL " or null pointer".
POSIX uses the term "null pointer", not "NULL pointer".
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2014-01-03 02:01:50 +00:00
|
|
|
Both \fIargv\fP and \fIenvp\fP must be terminated by a null pointer.
|
2007-04-12 22:42:49 +00:00
|
|
|
The argument vector and environment can be accessed by the
|
2007-04-30 09:00:59 +00:00
|
|
|
called program's main function, when it is defined as:
|
|
|
|
|
2007-12-19 06:57:44 +00:00
|
|
|
.in +4n
|
2007-04-30 09:00:59 +00:00
|
|
|
.nf
|
2007-07-18 20:24:30 +00:00
|
|
|
int main(int argc, char *argv[], char *envp[])
|
2007-04-30 09:00:59 +00:00
|
|
|
.fi
|
|
|
|
.in
|
2004-11-03 13:51:07 +00:00
|
|
|
|
2007-05-12 09:06:04 +00:00
|
|
|
.BR execve ()
|
|
|
|
does not return on success, and the text, data, bss, and
|
2004-11-03 13:51:07 +00:00
|
|
|
stack of the calling process are overwritten by that of the program
|
2007-04-12 22:42:49 +00:00
|
|
|
loaded.
|
2004-11-03 13:51:07 +00:00
|
|
|
|
|
|
|
If the current program is being ptraced, a \fBSIGTRAP\fP is sent to it
|
2007-05-12 09:06:04 +00:00
|
|
|
after a successful
|
|
|
|
.BR execve ().
|
2004-11-03 13:51:07 +00:00
|
|
|
|
2005-07-18 14:25:42 +00:00
|
|
|
If the set-user-ID bit is set on the program file pointed to by
|
2007-06-21 22:55:04 +00:00
|
|
|
\fIfilename\fP,
|
intro.1, time.1, access.2, acct.2, alloc_hugepages.2, bind.2, chdir.2, chmod.2, chown.2, chroot.2, clone.2, close.2, execve.2, fallocate.2, fcntl.2, getdents.2, getrusage.2, getxattr.2, init_module.2, inotify_add_watch.2, ioprio_set.2, kcmp.2, link.2, listxattr.2, lseek.2, madvise.2, mkdir.2, mknod.2, mmap.2, mount.2, move_pages.2, msgctl.2, nfsservctl.2, open.2, pivot_root.2, quotactl.2, read.2, readlink.2, removexattr.2, rename.2, rmdir.2, semctl.2, setfsgid.2, setfsuid.2, setresuid.2, setuid.2, setup.2, setxattr.2, shmctl.2, splice.2, spu_create.2, stat.2, statfs.2, swapon.2, symlink.2, sync.2, sync_file_range.2, sysfs.2, truncate.2, umount.2, unlink.2, unshare.2, ustat.2, utime.2, utimensat.2, write.2, btree.3, errno.3, fexecve.3, ftw.3, futimes.3, get_nprocs_conf.3, getcwd.3, getdirentries.3, getmntent.3, glob.3, mkfifo.3, mq_open.3, readdir.3, realpath.3, recno.3, remove.3, sem_open.3, shm_open.3, statvfs.3, sysconf.3, telldir.3, tmpfile.3, cciss.4, initrd.4, pts.4, sk98lin.4, vcs.4, core.5, filesystems.5, proc.5, boot.7, bootparam.7, capabilities.7, cpuset.7, credentials.7, feature_test_macros.7, fifo.7, hier.7, inotify.7, intro.7, mq_overview.7, path_resolution.7, pipe.7, sem_overview.7, shm_overview.7, spufs.7, symlink.7, unix.7, uri.7, sync.8: Global fix: s/file system/filesystem/
Notwithstanding 24d01c530c5a3f75217543d02bf6712395e5f90c,
"filesystem" is the form used by the great majority of man pages
outside the man-pages project and in a number of other sources,
so let's go with that.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-08-08 08:07:57 +00:00
|
|
|
and the underlying filesystem is not mounted
|
2007-09-20 16:26:31 +00:00
|
|
|
.I nosuid
|
2007-04-30 14:30:17 +00:00
|
|
|
(the
|
|
|
|
.B MS_NOSUID
|
|
|
|
flag for
|
|
|
|
.BR mount (2)),
|
|
|
|
and the calling process is not being ptraced,
|
Hi Andries,
> The question came up whether execve of a suid binary while being ptraced
> would fail or ignore the suid part. The answer today seems to be the
> latter:
>
> E.g. (in 2.6.11) security/dummy.c:
>
> static void dummy_bprm_apply_creds (struct linux_binprm *bprm, int
> unsafe)
> {
> if (bprm->e_uid != current->uid || bprm->e_gid != current->gid) {
> if ((unsafe & ~LSM_UNSAFE_PTRACE_CAP) &&
> !capable(CAP_SETUID)) {
> bprm->e_uid = current->uid;
> bprm->e_gid = current->gid;
> }
> }
> }
>
> and fs/exec.c:
>
> void compute_creds(struct linux_binprm *bprm) {
> int unsafe;
>
> unsafe = unsafe_exec(current);
> security_bprm_apply_creds(bprm, unsafe);
> }
>
> static inline int unsafe_exec(struct task_struct *p) {
> int unsafe = 0;
> if (p->ptrace & PT_PTRACED) {
> if (p->ptrace & PT_PTRACE_CAP)
> unsafe |= LSM_UNSAFE_PTRACE_CAP;
> else
> unsafe |= LSM_UNSAFE_PTRACE;
> }
> return unsafe;
> }
>
> That is: if the process that calls execve() is being traced,
> the LSM_UNSAFE_PTRACE bit is et in unsafe and security_bprm_apply_creds()
> will make sure the suid/sgid bits are ignored.
>
> ---
>
> In my man page I do not read anything like that. It says
>
> EPERM The process is being traced, the user is not the superuser and
> the file has an SUID or SGID bit set.
> and
>
> If the current program is being ptraced, a SIGTRAP is sent to it after
> a successful execve().
>
> If the set-uid bit is set on the program file pointed to by filename
> the effective user ID of the calling process is changed to that of the
> owner of the program file.
>
> So, maybe this sentence should be amended to read
>
> If the set-uid bit is set on the program file pointed to by filename
> and the current process is not being ptraced, the effective user ID
> of the calling process is changed to ...
I changed your "current" to "calling" (to be consistent with the
rest of the page), but otherwise applied as you suggest.
The revision will appear in man-pages-2.03, which I can release
any time now. Are you avialable to do an upload tomorrow?
2005-05-31 16:07:24 +00:00
|
|
|
then the effective user ID of the calling process is changed
|
2006-09-04 08:57:04 +00:00
|
|
|
to that of the owner of the program file.
|
2006-07-22 17:24:17 +00:00
|
|
|
Similarly, when the set-group-ID
|
2004-11-03 13:51:07 +00:00
|
|
|
bit of the program file is set the effective group ID of the calling
|
|
|
|
process is set to the group of the program file.
|
|
|
|
|
2006-07-22 17:24:17 +00:00
|
|
|
The effective user ID of the process is copied to the saved set-user-ID;
|
|
|
|
similarly, the effective group ID is copied to the saved set-group-ID.
|
2007-04-12 22:42:49 +00:00
|
|
|
This copying takes place after any effective ID changes that occur
|
2015-04-21 11:18:15 +00:00
|
|
|
because of the set-user-ID and set-group-ID mode bits.
|
2006-07-22 17:24:17 +00:00
|
|
|
|
2007-07-08 12:51:09 +00:00
|
|
|
If the executable is an a.out dynamically linked
|
2006-07-22 17:24:17 +00:00
|
|
|
binary executable containing
|
2004-11-03 13:51:07 +00:00
|
|
|
shared-library stubs, the Linux dynamic linker
|
|
|
|
.BR ld.so (8)
|
2007-04-12 22:42:49 +00:00
|
|
|
is called at the start of execution to bring
|
2006-07-22 17:24:17 +00:00
|
|
|
needed shared libraries into memory
|
2004-11-03 13:51:07 +00:00
|
|
|
and link the executable with them.
|
|
|
|
|
2007-07-08 12:51:09 +00:00
|
|
|
If the executable is a dynamically linked ELF executable, the
|
2004-11-03 13:51:07 +00:00
|
|
|
interpreter named in the PT_INTERP segment is used to load the needed
|
2007-04-12 22:42:49 +00:00
|
|
|
shared libraries.
|
|
|
|
This interpreter is typically
|
2012-05-04 23:23:57 +00:00
|
|
|
.I /lib/ld-linux.so.2
|
2014-06-29 12:37:46 +00:00
|
|
|
for binaries linked with glibc.
|
2006-09-04 12:27:37 +00:00
|
|
|
|
|
|
|
All process attributes are preserved during an
|
|
|
|
.BR execve (),
|
|
|
|
except the following:
|
2012-05-04 23:10:27 +00:00
|
|
|
.IP * 3
|
2007-04-12 22:42:49 +00:00
|
|
|
The dispositions of any signals that are being caught are
|
2010-01-05 14:07:22 +00:00
|
|
|
reset to the default
|
|
|
|
.RB ( signal (7)).
|
2007-12-25 21:41:35 +00:00
|
|
|
.IP *
|
2006-09-04 12:27:37 +00:00
|
|
|
Any alternate signal stack is not preserved
|
|
|
|
.RB ( sigaltstack (2)).
|
2007-12-25 21:41:35 +00:00
|
|
|
.IP *
|
2006-09-04 12:27:37 +00:00
|
|
|
Memory mappings are not preserved
|
|
|
|
.RB ( mmap (2)).
|
2007-12-25 21:41:35 +00:00
|
|
|
.IP *
|
clone.2, execve.2, getpriority.2, ipc.2, kcmp.2, killpg.2, msgctl.2, msgget.2, msgop.2, select.2, semctl.2, semget.2, semop.2, setpgid.2, shmctl.2, shmget.2, shmop.2, sigaction.2, signal.2, socket.2, socketpair.2, syscalls.2, umask.2, unshare.2: ffix: Don't allow line break inside "System V"
2014-04-28 07:36:03 +00:00
|
|
|
Attached System\ V shared memory segments are detached
|
2006-09-04 12:27:37 +00:00
|
|
|
.RB ( shmat (2)).
|
2007-12-25 21:41:35 +00:00
|
|
|
.IP *
|
2006-09-04 12:27:37 +00:00
|
|
|
POSIX shared memory regions are unmapped
|
|
|
|
.RB ( shm_open (3)).
|
2007-12-25 21:41:35 +00:00
|
|
|
.IP *
|
2006-09-04 12:27:37 +00:00
|
|
|
Open POSIX message queue descriptors are closed
|
|
|
|
.RB ( mq_overview (7)).
|
2007-12-25 21:41:35 +00:00
|
|
|
.IP *
|
2006-09-04 12:27:37 +00:00
|
|
|
Any open POSIX named semaphores are closed
|
|
|
|
.RB ( sem_overview (7)).
|
2007-12-25 21:41:35 +00:00
|
|
|
.IP *
|
2006-09-04 12:27:37 +00:00
|
|
|
POSIX timers are not preserved
|
clock_nanosleep.2, execve.2, fork.2, nanosleep.2, sigaction.2, timerfd_create.2, pthread_getcpuclockid.3, ualarm.3, usleep.3, pthreads.7, time.7: Global fix: s/(3)/(2)/ in section number xrefs for timer_*() API
The POSIX timers API is implemented (mostly) within the kernel,
so thse interfaces are system calls. Although there are as yet
no man pages, when they are added they should be in Section 2,
not 3. Therefore fix those pages that currently refer to these
interfaces as being in Section 3.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2009-02-07 20:21:03 +00:00
|
|
|
.RB ( timer_create (2)).
|
2007-12-25 21:41:35 +00:00
|
|
|
.IP *
|
2006-09-04 12:27:37 +00:00
|
|
|
Any open directory streams are closed
|
|
|
|
.RB ( opendir (3)).
|
2007-12-25 21:41:35 +00:00
|
|
|
.IP *
|
2006-09-04 12:27:37 +00:00
|
|
|
Memory locks are not preserved
|
|
|
|
.RB ( mlock (2),
|
|
|
|
.BR mlockall (2)).
|
2007-12-25 21:41:35 +00:00
|
|
|
.IP *
|
2006-09-04 12:27:37 +00:00
|
|
|
Exit handlers are not preserved
|
|
|
|
.RB ( atexit (3),
|
|
|
|
.BR on_exit (3)).
|
2008-08-07 10:54:18 +00:00
|
|
|
.IP *
|
|
|
|
The floating-point environment is reset to the default (see
|
|
|
|
.BR fenv (3)).
|
2006-09-04 12:27:37 +00:00
|
|
|
.PP
|
2007-04-12 22:42:49 +00:00
|
|
|
The process attributes in the preceding list are all specified
|
2015-04-18 05:05:11 +00:00
|
|
|
in POSIX.1.
|
2007-04-12 22:42:49 +00:00
|
|
|
The following Linux-specific process attributes are also
|
2006-09-04 12:27:37 +00:00
|
|
|
not preserved during an
|
|
|
|
.BR execve ():
|
2007-12-25 21:41:35 +00:00
|
|
|
.IP * 3
|
2007-04-12 22:42:49 +00:00
|
|
|
The
|
2006-09-04 12:27:37 +00:00
|
|
|
.BR prctl (2)
|
2007-04-12 22:42:49 +00:00
|
|
|
.B PR_SET_DUMPABLE
|
2006-09-04 12:27:37 +00:00
|
|
|
flag is set,
|
|
|
|
unless a set-user-ID or set-group ID program is being executed,
|
|
|
|
in which case it is cleared.
|
2007-12-25 21:41:35 +00:00
|
|
|
.IP *
|
2007-04-12 22:42:49 +00:00
|
|
|
The
|
2006-09-04 12:27:37 +00:00
|
|
|
.BR prctl (2)
|
|
|
|
.B PR_SET_KEEPCAPS
|
|
|
|
flag is cleared.
|
2007-12-25 21:41:35 +00:00
|
|
|
.IP *
|
2012-10-27 04:28:48 +00:00
|
|
|
(Since Linux 2.4.36 / 2.6.23)
|
|
|
|
If a set-user-ID or set-group-ID program is being executed,
|
|
|
|
then the parent death signal set by
|
|
|
|
.BR prctl (2)
|
|
|
|
.B PR_SET_PDEATHSIG
|
|
|
|
flag is cleared.
|
|
|
|
.IP *
|
2006-09-13 14:08:11 +00:00
|
|
|
The process name, as set by
|
|
|
|
.BR prctl (2)
|
2007-09-20 16:26:31 +00:00
|
|
|
.B PR_SET_NAME
|
2006-09-13 14:08:11 +00:00
|
|
|
(and displayed by
|
2008-06-26 13:28:19 +00:00
|
|
|
.IR "ps\ \-o comm" ),
|
2006-09-13 14:08:11 +00:00
|
|
|
is reset to the name of the new executable file.
|
2007-12-25 21:41:35 +00:00
|
|
|
.IP *
|
2012-10-27 04:29:16 +00:00
|
|
|
The
|
|
|
|
.B SECBIT_KEEP_CAPS
|
|
|
|
.I securebits
|
|
|
|
flag is cleared.
|
|
|
|
See
|
|
|
|
.BR capabilities (7).
|
|
|
|
.IP *
|
2007-06-21 05:38:48 +00:00
|
|
|
The termination signal is reset to
|
|
|
|
.B SIGCHLD
|
2006-09-04 12:27:37 +00:00
|
|
|
(see
|
|
|
|
.BR clone (2)).
|
2013-05-06 06:14:41 +00:00
|
|
|
.IP *
|
|
|
|
The file descriptor table is unshared, undoing the effect of the
|
|
|
|
.B CLONE_FILES
|
|
|
|
flag of
|
|
|
|
.BR clone (2).
|
2006-09-04 12:27:37 +00:00
|
|
|
.PP
|
|
|
|
Note the following further points:
|
2007-12-25 21:41:35 +00:00
|
|
|
.IP * 3
|
2007-04-30 08:55:57 +00:00
|
|
|
All threads other than the calling thread are destroyed during an
|
2006-09-04 12:27:37 +00:00
|
|
|
.BR execve ().
|
|
|
|
Mutexes, condition variables, and other pthreads objects are not preserved.
|
2007-12-25 21:41:35 +00:00
|
|
|
.IP *
|
2006-09-04 12:27:37 +00:00
|
|
|
The equivalent of \fIsetlocale(LC_ALL, "C")\fP
|
|
|
|
is executed at program start-up.
|
2007-12-25 21:41:35 +00:00
|
|
|
.IP *
|
2015-04-18 05:05:11 +00:00
|
|
|
POSIX.1 specifies that the dispositions of any signals that
|
2006-09-04 12:27:37 +00:00
|
|
|
are ignored or set to the default are left unchanged.
|
2015-04-18 05:05:11 +00:00
|
|
|
POSIX.1 specifies one exception: if
|
2007-06-21 05:38:48 +00:00
|
|
|
.B SIGCHLD
|
|
|
|
is being ignored,
|
2007-04-12 22:42:49 +00:00
|
|
|
then an implementation may leave the disposition unchanged or
|
2006-09-04 12:27:37 +00:00
|
|
|
reset it to the default; Linux does the former.
|
2007-12-25 21:41:35 +00:00
|
|
|
.IP *
|
2007-06-08 09:56:56 +00:00
|
|
|
Any outstanding asynchronous I/O operations are canceled
|
2006-09-04 12:27:37 +00:00
|
|
|
.RB ( aio_read (3),
|
|
|
|
.BR aio_write (3)).
|
2007-12-25 21:41:35 +00:00
|
|
|
.IP *
|
2007-04-12 22:42:49 +00:00
|
|
|
For the handling of capabilities during
|
2007-11-24 10:10:39 +00:00
|
|
|
.BR execve (),
|
2006-09-04 12:27:37 +00:00
|
|
|
see
|
|
|
|
.BR capabilities (7).
|
2007-12-25 21:41:35 +00:00
|
|
|
.IP *
|
2007-06-21 22:55:04 +00:00
|
|
|
By default, file descriptors remain open across an
|
2007-04-30 14:30:17 +00:00
|
|
|
.BR execve ().
|
2007-11-21 18:17:59 +00:00
|
|
|
File descriptors that are marked close-on-exec are closed;
|
|
|
|
see the description of
|
2007-09-20 16:26:31 +00:00
|
|
|
.B FD_CLOEXEC
|
2007-04-30 14:30:17 +00:00
|
|
|
in
|
|
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|
.BR fcntl (2).
|
|
|
|
(If a file descriptor is closed, this will cause the release
|
|
|
|
of all record locks obtained on the underlying file by this process.
|
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|
See
|
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|
|
.BR fcntl (2)
|
|
|
|
for details.)
|
2015-04-18 05:05:11 +00:00
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|
POSIX.1 says that if file descriptors 0, 1, and 2 would
|
2007-04-30 14:30:17 +00:00
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otherwise be closed after a successful
|
|
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.BR execve (),
|
|
|
|
and the process would gain privilege because the set-user_ID or
|
2015-04-21 11:18:15 +00:00
|
|
|
set-group_ID mode bit was set on the executed file,
|
2007-04-30 14:30:17 +00:00
|
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|
then the system may open an unspecified file for each of these
|
|
|
|
file descriptors.
|
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|
|
As a general principle, no portable program, whether privileged or not,
|
2007-06-21 22:55:04 +00:00
|
|
|
can assume that these three file descriptors will remain
|
2007-04-30 14:30:17 +00:00
|
|
|
closed across an
|
|
|
|
.BR execve ().
|
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|
.\" On Linux it appears that these file descriptors are
|
|
|
|
.\" always open after an execve(), and it looks like
|
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|
|
.\" Solaris 8 and FreeBSD 6.1 are the same. -- mtk, 30 Apr 2007
|
2007-04-30 12:25:52 +00:00
|
|
|
.SS Interpreter scripts
|
2007-06-21 22:55:04 +00:00
|
|
|
An interpreter script is a text file that has execute
|
2007-04-30 12:25:52 +00:00
|
|
|
permission enabled and whose first line is of the form:
|
|
|
|
|
2007-12-19 06:57:44 +00:00
|
|
|
.in +4n
|
2007-04-30 12:25:52 +00:00
|
|
|
.nf
|
2007-07-18 20:24:30 +00:00
|
|
|
\fB#!\fP \fIinterpreter \fP[optional-arg]
|
2007-04-30 12:25:52 +00:00
|
|
|
.fi
|
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|
|
.in
|
|
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|
|
2007-06-21 22:55:04 +00:00
|
|
|
The
|
|
|
|
.I interpreter
|
2007-04-30 12:25:52 +00:00
|
|
|
must be a valid pathname for an
|
|
|
|
executable which is not itself a script.
|
2007-06-21 22:55:04 +00:00
|
|
|
If the
|
2007-04-30 12:25:52 +00:00
|
|
|
.I filename
|
|
|
|
argument of
|
|
|
|
.BR execve ()
|
2007-06-21 22:55:04 +00:00
|
|
|
specifies an interpreter script, then
|
2007-04-30 12:25:52 +00:00
|
|
|
.I interpreter
|
|
|
|
will be invoked with the following arguments:
|
|
|
|
|
2007-12-19 06:57:44 +00:00
|
|
|
.in +4n
|
2007-04-30 12:25:52 +00:00
|
|
|
.nf
|
2007-07-18 20:24:30 +00:00
|
|
|
\fIinterpreter\fP [optional-arg] \fIfilename\fP arg...
|
2007-04-30 12:25:52 +00:00
|
|
|
.fi
|
|
|
|
.in
|
|
|
|
|
|
|
|
where
|
|
|
|
.I arg...
|
2007-06-21 22:55:04 +00:00
|
|
|
is the series of words pointed to by the
|
2007-04-30 12:25:52 +00:00
|
|
|
.I argv
|
2007-06-21 22:55:04 +00:00
|
|
|
argument of
|
2013-10-25 17:45:46 +00:00
|
|
|
.BR execve (),
|
|
|
|
starting at
|
|
|
|
.IR argv [1].
|
2007-04-30 12:25:52 +00:00
|
|
|
|
|
|
|
For portable use,
|
|
|
|
.I optional-arg
|
|
|
|
should either be absent, or be specified as a single word (i.e., it
|
|
|
|
should not contain white space); see NOTES below.
|
intro.1, time.1, _syscall.2, accept.2, capget.2, clone.2, execve.2, fcntl.2, intro.2, ioctl_list.2, ioprio_set.2, kill.2, mlock.2, nanosleep.2, perf_event_open.2, select.2, stat.2, times.2, ustat.2, vfork.2, wait.2, cfree.3, dbopen.3, dlopen.3, fenv.3, fmtmsg.3, gamma.3, getaddrinfo.3, gethostbyname.3, getnameinfo.3, getspnam.3, login.3, printf.3, regex.3, stdio.3, sysconf.3, termios.3, ttyslot.3, undocumented.3, wordexp.3, console_codes.4, initrd.4, mouse.4, random.4, st.4, tty_ioctl.4, wavelan.4, charmap.5, dir_colors.5, hosts.5, termcap.5, armscii-8.7, boot.7, bootparam.7, capabilities.7, charsets.7, ddp.7, futex.7, glob.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, man.7, numa.7, path_resolution.7, pipe.7, posixoptions.7, pthreads.7, pty.7, rtnetlink.7, signal.7, time.7, udp.7, udplite.7, unicode.7, uri.7, utf-8.7: G;lobal fix: remove unneeded double quotes in .SS headings
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-02-24 18:02:18 +00:00
|
|
|
.SS Limits on size of arguments and environment
|
intro.1, time.1, accept.2, bind.2, connect.2, execve.2, flock.2, getdents.2, getpriority.2, getuid.2, intro.2, ioctl.2, mincore.2, mknod.2, personality.2, ptrace.2, read.2, recv.2, select_tut.2, send.2, sendfile.2, shmctl.2, sigaction.2, signal.2, stat.2, times.2, truncate.2, umask.2, wait.2, MB_CUR_MAX.3, MB_LEN_MAX.3, argz_add.3, btowc.3, clearenv.3, clock.3, cmsg.3, end.3, endian.3, errno.3, exit.3, fgetwc.3, fgetws.3, fopen.3, fputwc.3, fputws.3, fseek.3, fwide.3, getfsent.3, getgrnam.3, gethostid.3, getipnodebyname.3, getmntent.3, getpwnam.3, getwchar.3, grantpt.3, iconv.3, iconv_close.3, iconv_open.3, insque.3, intro.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, malloc.3, mblen.3, mbrlen.3, mbrtowc.3, mbsinit.3, mbsnrtowcs.3, mbsrtowcs.3, mbstowcs.3, mbtowc.3, mkstemp.3, mktemp.3, nl_langinfo.3, openpty.3, posix_openpt.3, printf.3, ptsname.3, putwchar.3, qecvt.3, rcmd.3, readdir.3, rexec.3, rpc.3, setnetgrent.3, shm_open.3, sigpause.3, stdin.3, stpcpy.3, strftime.3, strptime.3, syslog.3, towctrans.3, towlower.3, towupper.3, ttyslot.3, ungetwc.3, unlocked_stdio.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, 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, wprintf.3, console_ioctl.4, pts.4, elf.5, filesystems.5, hosts.5, proc.5, ttytype.5, boot.7, capabilities.7, credentials.7, epoll.7, glob.7, koi8-r.7, path_resolution.7, pty.7, signal.7, suffixes.7, time.7, unicode.7, unix.7, uri.7, utf-8.7: global fix: s/Unix/UNIX/
The man pages were rather inconsistent in the use of "Unix"
versus "UNIX". Let's go with the trademark usage.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2010-10-12 04:45:38 +00:00
|
|
|
Most UNIX implementations impose some limit on the total size
|
2007-09-10 04:31:59 +00:00
|
|
|
of the command-line argument
|
|
|
|
.RI ( argv )
|
|
|
|
and environment
|
|
|
|
.RI ( envp )
|
|
|
|
strings that may be passed to a new program.
|
|
|
|
POSIX.1 allows an implementation to advertise this limit using the
|
2007-09-20 16:26:31 +00:00
|
|
|
.B ARG_MAX
|
2007-09-10 04:31:59 +00:00
|
|
|
constant (either defined in
|
|
|
|
.I <limits.h>
|
|
|
|
or available at run time using the call
|
|
|
|
.IR "sysconf(_SC_ARG_MAX)" ).
|
|
|
|
|
|
|
|
On Linux prior to kernel 2.6.23, the memory used to store the
|
|
|
|
environment and argument strings was limited to 32 pages
|
|
|
|
(defined by the kernel constant
|
|
|
|
.BR MAX_ARG_PAGES ).
|
|
|
|
On architectures with a 4-kB page size,
|
|
|
|
this yields a maximum size of 128 kB.
|
|
|
|
|
|
|
|
On kernel 2.6.23 and later, most architectures support a size limit
|
|
|
|
derived from the soft
|
|
|
|
.B RLIMIT_STACK
|
|
|
|
resource limit (see
|
2008-02-22 15:18:34 +00:00
|
|
|
.BR getrlimit (2))
|
|
|
|
that is in force at the time of the
|
|
|
|
.BR execve ()
|
|
|
|
call.
|
2008-10-05 03:57:52 +00:00
|
|
|
(Architectures with no memory management unit are excepted:
|
|
|
|
they maintain the limit that was in effect before kernel 2.6.23.)
|
|
|
|
This change allows programs to have a much larger
|
2007-09-10 04:31:59 +00:00
|
|
|
argument and/or environment list.
|
2008-10-05 03:57:52 +00:00
|
|
|
.\" For some background on the changes to ARG_MAX in kernels 2.6.23 and
|
|
|
|
.\" 2.6.25, see:
|
|
|
|
.\" http://sourceware.org/bugzilla/show_bug.cgi?id=5786
|
|
|
|
.\" http://bugzilla.kernel.org/show_bug.cgi?id=10095
|
|
|
|
.\" http://thread.gmane.org/gmane.linux.kernel/646709/focus=648101,
|
|
|
|
.\" checked into 2.6.25 as commit a64e715fc74b1a7dcc5944f848acc38b2c4d4ee2.
|
|
|
|
For these architectures, the total size is limited to 1/4 of the allowed
|
|
|
|
stack size.
|
|
|
|
(Imposing the 1/4-limit
|
2007-09-10 04:31:59 +00:00
|
|
|
ensures that the new program always has some stack space.)
|
|
|
|
.\" Ollie: That doesn't include the lists of pointers, though,
|
|
|
|
.\" so the actual usage is a bit higher (1 pointer per argument).
|
2008-10-05 03:57:52 +00:00
|
|
|
Since Linux 2.6.25,
|
|
|
|
the kernel places a floor of 32 pages on this size limit,
|
|
|
|
so that, even when
|
|
|
|
.BR RLIMIT_STACK
|
|
|
|
is set very low,
|
|
|
|
applications are guaranteed to have at least as much argument and
|
|
|
|
environment space as was provided by Linux 2.6.23 and earlier.
|
|
|
|
(This guarantee was not provided in Linux 2.6.23 and 2.6.24.)
|
|
|
|
Additionally, the limit per string is 32 pages (the kernel constant
|
|
|
|
.BR MAX_ARG_STRLEN ),
|
|
|
|
and the maximum number of strings is 0x7FFFFFFF.
|
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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2007-05-12 09:06:04 +00:00
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On success,
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.BR execve ()
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does not return, on error \-1 is returned, and
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2004-11-03 13:51:07 +00:00
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.I errno
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is set appropriately.
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.SH ERRORS
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.TP
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.B E2BIG
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2007-04-12 22:42:49 +00:00
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The total number of bytes in the environment
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2005-11-08 15:25:07 +00:00
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.RI ( envp )
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2007-04-12 22:42:49 +00:00
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and argument list
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2005-11-08 15:25:07 +00:00
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.RI ( argv )
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is too large.
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2004-11-03 13:51:07 +00:00
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.TP
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.B EACCES
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Search permission is denied on a component of the path prefix of
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.I filename
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or the name of a script interpreter.
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(See also
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2007-05-26 12:41:39 +00:00
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.BR path_resolution (7).)
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2004-11-03 13:51:07 +00:00
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.TP
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.B EACCES
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The file or a script interpreter is not a regular file.
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.TP
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.B EACCES
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Execute permission is denied for the file or a script or ELF interpreter.
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.TP
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.B EACCES
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intro.1, time.1, access.2, acct.2, alloc_hugepages.2, bind.2, chdir.2, chmod.2, chown.2, chroot.2, clone.2, close.2, execve.2, fallocate.2, fcntl.2, getdents.2, getrusage.2, getxattr.2, init_module.2, inotify_add_watch.2, ioprio_set.2, kcmp.2, link.2, listxattr.2, lseek.2, madvise.2, mkdir.2, mknod.2, mmap.2, mount.2, move_pages.2, msgctl.2, nfsservctl.2, open.2, pivot_root.2, quotactl.2, read.2, readlink.2, removexattr.2, rename.2, rmdir.2, semctl.2, setfsgid.2, setfsuid.2, setresuid.2, setuid.2, setup.2, setxattr.2, shmctl.2, splice.2, spu_create.2, stat.2, statfs.2, swapon.2, symlink.2, sync.2, sync_file_range.2, sysfs.2, truncate.2, umount.2, unlink.2, unshare.2, ustat.2, utime.2, utimensat.2, write.2, btree.3, errno.3, fexecve.3, ftw.3, futimes.3, get_nprocs_conf.3, getcwd.3, getdirentries.3, getmntent.3, glob.3, mkfifo.3, mq_open.3, readdir.3, realpath.3, recno.3, remove.3, sem_open.3, shm_open.3, statvfs.3, sysconf.3, telldir.3, tmpfile.3, cciss.4, initrd.4, pts.4, sk98lin.4, vcs.4, core.5, filesystems.5, proc.5, boot.7, bootparam.7, capabilities.7, cpuset.7, credentials.7, feature_test_macros.7, fifo.7, hier.7, inotify.7, intro.7, mq_overview.7, path_resolution.7, pipe.7, sem_overview.7, shm_overview.7, spufs.7, symlink.7, unix.7, uri.7, sync.8: Global fix: s/file system/filesystem/
Notwithstanding 24d01c530c5a3f75217543d02bf6712395e5f90c,
"filesystem" is the form used by the great majority of man pages
outside the man-pages project and in a number of other sources,
so let's go with that.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-08-08 08:07:57 +00:00
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The filesystem is mounted
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2004-11-03 13:51:07 +00:00
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.IR noexec .
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.TP
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2014-05-14 14:05:34 +00:00
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.BR EAGAIN " (since Linux 3.1)"
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.\" commit 72fa59970f8698023045ab0713d66f3f4f96945c
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Having changed its real UID using one of the
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.BR set*uid ()
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calls, the caller was\(emand is now still\(emabove its
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.BR RLIMIT_NPROC
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resource limit (see
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.BR setrlimit (2)).
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For a more detailed explanation of this error, see NOTES.
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.TP
|
2004-11-03 13:51:07 +00:00
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.B EFAULT
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.I filename
|
2014-01-07 18:52:49 +00:00
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or one of the pointers in the vectors
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.I argv
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or
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.I envp
|
2004-11-03 13:51:07 +00:00
|
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points outside your accessible address space.
|
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.TP
|
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.B EINVAL
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An ELF executable had more than one PT_INTERP segment (i.e., tried to
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name more than one interpreter).
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.TP
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.B EIO
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An I/O error occurred.
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.TP
|
|
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.B EISDIR
|
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|
An ELF interpreter was a directory.
|
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.TP
|
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.B ELIBBAD
|
2007-06-08 09:56:56 +00:00
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An ELF interpreter was not in a recognized format.
|
2004-11-03 13:51:07 +00:00
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.TP
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.B ELOOP
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Too many symbolic links were encountered in resolving
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.I filename
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or the name of a script or ELF interpreter.
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.TP
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.B EMFILE
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The process has the maximum number of files open.
|
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.TP
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.B ENAMETOOLONG
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.I filename
|
|
|
|
is too long.
|
|
|
|
.TP
|
|
|
|
.B ENFILE
|
|
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The system limit on the total number of open files has been reached.
|
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.TP
|
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.B ENOENT
|
2007-04-12 22:42:49 +00:00
|
|
|
The file
|
2004-11-03 13:51:07 +00:00
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|
.I filename
|
|
|
|
or a script or ELF interpreter does not exist, or a shared library
|
2015-05-11 10:14:54 +00:00
|
|
|
.\" FIXME but see http://sourceware.org/bugzilla/show_bug.cgi?id=12241
|
2004-11-03 13:51:07 +00:00
|
|
|
needed for file or interpreter cannot be found.
|
|
|
|
.TP
|
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|
.B ENOEXEC
|
2007-06-08 09:56:56 +00:00
|
|
|
An executable is not in a recognized format, is for the wrong
|
2004-11-03 13:51:07 +00:00
|
|
|
architecture, or has some other format error that means it cannot be
|
|
|
|
executed.
|
|
|
|
.TP
|
|
|
|
.B ENOMEM
|
|
|
|
Insufficient kernel memory was available.
|
|
|
|
.TP
|
|
|
|
.B ENOTDIR
|
|
|
|
A component of the path prefix of
|
|
|
|
.I filename
|
|
|
|
or a script or ELF interpreter is not a directory.
|
|
|
|
.TP
|
|
|
|
.B EPERM
|
intro.1, time.1, access.2, acct.2, alloc_hugepages.2, bind.2, chdir.2, chmod.2, chown.2, chroot.2, clone.2, close.2, execve.2, fallocate.2, fcntl.2, getdents.2, getrusage.2, getxattr.2, init_module.2, inotify_add_watch.2, ioprio_set.2, kcmp.2, link.2, listxattr.2, lseek.2, madvise.2, mkdir.2, mknod.2, mmap.2, mount.2, move_pages.2, msgctl.2, nfsservctl.2, open.2, pivot_root.2, quotactl.2, read.2, readlink.2, removexattr.2, rename.2, rmdir.2, semctl.2, setfsgid.2, setfsuid.2, setresuid.2, setuid.2, setup.2, setxattr.2, shmctl.2, splice.2, spu_create.2, stat.2, statfs.2, swapon.2, symlink.2, sync.2, sync_file_range.2, sysfs.2, truncate.2, umount.2, unlink.2, unshare.2, ustat.2, utime.2, utimensat.2, write.2, btree.3, errno.3, fexecve.3, ftw.3, futimes.3, get_nprocs_conf.3, getcwd.3, getdirentries.3, getmntent.3, glob.3, mkfifo.3, mq_open.3, readdir.3, realpath.3, recno.3, remove.3, sem_open.3, shm_open.3, statvfs.3, sysconf.3, telldir.3, tmpfile.3, cciss.4, initrd.4, pts.4, sk98lin.4, vcs.4, core.5, filesystems.5, proc.5, boot.7, bootparam.7, capabilities.7, cpuset.7, credentials.7, feature_test_macros.7, fifo.7, hier.7, inotify.7, intro.7, mq_overview.7, path_resolution.7, pipe.7, sem_overview.7, shm_overview.7, spufs.7, symlink.7, unix.7, uri.7, sync.8: Global fix: s/file system/filesystem/
Notwithstanding 24d01c530c5a3f75217543d02bf6712395e5f90c,
"filesystem" is the form used by the great majority of man pages
outside the man-pages project and in a number of other sources,
so let's go with that.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-08-08 08:07:57 +00:00
|
|
|
The filesystem is mounted
|
2004-11-03 13:51:07 +00:00
|
|
|
.IR nosuid ,
|
2007-04-12 22:42:49 +00:00
|
|
|
the user is not the superuser,
|
2006-09-06 15:23:31 +00:00
|
|
|
and the file has the set-user-ID or set-group-ID bit set.
|
2004-11-03 13:51:07 +00:00
|
|
|
.TP
|
|
|
|
.B EPERM
|
|
|
|
The process is being traced, the user is not the superuser and the
|
2006-09-06 15:23:31 +00:00
|
|
|
file has the set-user-ID or set-group-ID bit set.
|
2004-11-03 13:51:07 +00:00
|
|
|
.TP
|
|
|
|
.B ETXTBSY
|
|
|
|
Executable was open for writing by one or more processes.
|
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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2015-04-18 05:05:11 +00:00
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POSIX.1-2001, POSIX.1-2008, SVr4, 4.3BSD.
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2015-04-18 05:06:07 +00:00
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POSIX does not document the #! behavior, but it exists
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(with some variations) on other UNIX systems.
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2006-08-03 13:57:17 +00:00
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.\" SVr4 documents additional error
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.\" conditions EAGAIN, EINTR, ELIBACC, ENOLINK, EMULTIHOP; POSIX does not
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.\" document ETXTBSY, EPERM, EFAULT, ELOOP, EIO, ENFILE, EMFILE, EINVAL,
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.\" EISDIR or ELIBBAD error conditions.
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2004-11-03 13:51:07 +00:00
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.SH NOTES
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2007-05-11 23:07:02 +00:00
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Set-user-ID and set-group-ID processes can not be
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.BR ptrace (2)d.
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2004-11-03 13:51:07 +00:00
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intro.1, time.1, access.2, acct.2, alloc_hugepages.2, bind.2, chdir.2, chmod.2, chown.2, chroot.2, clone.2, close.2, execve.2, fallocate.2, fcntl.2, getdents.2, getrusage.2, getxattr.2, init_module.2, inotify_add_watch.2, ioprio_set.2, kcmp.2, link.2, listxattr.2, lseek.2, madvise.2, mkdir.2, mknod.2, mmap.2, mount.2, move_pages.2, msgctl.2, nfsservctl.2, open.2, pivot_root.2, quotactl.2, read.2, readlink.2, removexattr.2, rename.2, rmdir.2, semctl.2, setfsgid.2, setfsuid.2, setresuid.2, setuid.2, setup.2, setxattr.2, shmctl.2, splice.2, spu_create.2, stat.2, statfs.2, swapon.2, symlink.2, sync.2, sync_file_range.2, sysfs.2, truncate.2, umount.2, unlink.2, unshare.2, ustat.2, utime.2, utimensat.2, write.2, btree.3, errno.3, fexecve.3, ftw.3, futimes.3, get_nprocs_conf.3, getcwd.3, getdirentries.3, getmntent.3, glob.3, mkfifo.3, mq_open.3, readdir.3, realpath.3, recno.3, remove.3, sem_open.3, shm_open.3, statvfs.3, sysconf.3, telldir.3, tmpfile.3, cciss.4, initrd.4, pts.4, sk98lin.4, vcs.4, core.5, filesystems.5, proc.5, boot.7, bootparam.7, capabilities.7, cpuset.7, credentials.7, feature_test_macros.7, fifo.7, hier.7, inotify.7, intro.7, mq_overview.7, path_resolution.7, pipe.7, sem_overview.7, shm_overview.7, spufs.7, symlink.7, unix.7, uri.7, sync.8: Global fix: s/file system/filesystem/
Notwithstanding 24d01c530c5a3f75217543d02bf6712395e5f90c,
"filesystem" is the form used by the great majority of man pages
outside the man-pages project and in a number of other sources,
so let's go with that.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-08-08 08:07:57 +00:00
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The result of mounting a filesystem
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2004-11-03 13:51:07 +00:00
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.I nosuid
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2007-04-30 14:30:17 +00:00
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varies across Linux kernel versions:
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2007-04-12 22:42:49 +00:00
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some will refuse execution of set-user-ID and set-group-ID
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2006-09-06 15:23:31 +00:00
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executables when this would
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2007-06-22 17:16:20 +00:00
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give the user powers she did not have already (and return
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.BR EPERM ),
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2007-04-12 22:42:49 +00:00
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some will just ignore the set-user-ID and set-group-ID bits and
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2005-10-20 15:11:10 +00:00
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.BR exec ()
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successfully.
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2015-05-11 07:04:55 +00:00
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2014-05-04 19:11:16 +00:00
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On Linux,
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2007-04-30 10:39:32 +00:00
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.I argv
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2014-05-04 19:11:16 +00:00
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and
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execve: Add envp to the Linux notes about NULL pointers
During the review of static analysis results, we discovered a
functional, but non-portable, use of execve(). For example:
char *cmd[] = { "/path/to/some/file", NULL };
execve(cmd[0], cmd, NULL);
The call succeeds. Yet, the static analysis tool (rightly)
pointed out that envp could be dereferenced. But digging into
glibc and the kernel, it appears that like argv, envp when NULL
is treated as if it were an empty list.
So, to clear things up, I'm submitting this patch to update the
man page to indicate that envp is treated like argv.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-06-13 18:37:28 +00:00
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.I envp
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2014-05-04 19:11:16 +00:00
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can be specified as NULL.
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In both cases, this has the same effect as specifying the argument
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epoll_ctl.2, execve.2, recv.2, timer_create.2, wait.2, argz_add.3, basename.3, dlopen.3, exec.3, fopencookie.3, fts.3, getaddrinfo.3, getcwd.3, gethostbyname.3, getifaddrs.3, getipnodebyname.3, getlogin.3, getnetent.3, getprotoent.3, getrpcent.3, getservent.3, getusershell.3, glob.3, if_nameindex.3, inet_ntop.3, lio_listio.3, mblen.3, mbrlen.3, mbrtowc.3, mbsinit.3, mbsnrtowcs.3, mbsrtowcs.3, mbstowcs.3, mq_notify.3, ptsname.3, realpath.3, setnetgrent.3, sigvec.3, strsignal.3, strtok.3, wcrtomb.3, wcsnrtombs.3, wcsrtombs.3, wcstombs.3, xdr.3: Global fix of "NULL pointer"
Change "NULL pointer: to "NUL " or null pointer".
POSIX uses the term "null pointer", not "NULL pointer".
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2014-01-03 02:01:50 +00:00
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as a pointer to a list containing a single null pointer.
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2015-05-11 06:59:50 +00:00
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.B "Do not take advantage of this nonstandard and nonportable misfeature!"
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On many other UNIX systems, specifying
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.I argv
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as NULL will result in an error
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2008-06-12 10:11:21 +00:00
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.RB ( EFAULT ).
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2015-05-11 06:59:50 +00:00
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.I Some
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other UNIX systems treat the
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.I envp==NULL
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case the same as Linux.
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2007-06-08 11:56:22 +00:00
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.\" e.g., EFAULT on Solaris 8 and FreeBSD 6.1; but
|
2007-04-30 10:39:32 +00:00
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.\" HP-UX 11 is like Linux -- mtk, Apr 2007
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.\" Bug filed 30 Apr 2007: http://bugzilla.kernel.org/show_bug.cgi?id=8408
|
2008-10-03 04:04:03 +00:00
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.\" Bug rejected (because fix would constitute an ABI change).
|
2007-04-30 10:39:32 +00:00
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.\"
|
2008-10-05 03:59:32 +00:00
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2015-04-18 05:05:11 +00:00
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POSIX.1 says that values returned by
|
2008-10-05 03:59:32 +00:00
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.BR sysconf (3)
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should be invariant over the lifetime of a process.
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However, since Linux 2.6.23, if the
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.BR RLIMIT_STACK
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resource limit changes, then the value reported by
|
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.B _SC_ARG_MAX
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will also change,
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to reflect the fact that the limit on space for holding
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command-line arguments and environment variables has changed.
|
2014-05-04 19:26:02 +00:00
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In most cases where
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.BR execve ()
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fails, control returns to the original executable image,
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and the caller of
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.BR execve ()
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can then handle the error.
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However, in (rare) cases (typically caused by resource exhaustion),
|
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failure may occur past the point of no return:
|
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|
the original executable image has been torn down,
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|
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|
but the new image could not be completely built.
|
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In such cases, the kernel kills the process with a
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|
|
.BR SIGKILL
|
|
|
|
signal.
|
2014-05-15 12:58:48 +00:00
|
|
|
.\"
|
|
|
|
.SS Interpreter scripts
|
|
|
|
A maximum line length of 127 characters is allowed for the first line in
|
2014-05-15 13:00:02 +00:00
|
|
|
an interpreter scripts.
|
2014-05-15 12:58:48 +00:00
|
|
|
|
|
|
|
The semantics of the
|
|
|
|
.I optional-arg
|
|
|
|
argument of an interpreter script vary across implementations.
|
|
|
|
On Linux, the entire string following the
|
|
|
|
.I interpreter
|
|
|
|
name is passed as a single argument to the interpreter,
|
|
|
|
and this string can include white space.
|
|
|
|
However, behavior differs on some other systems.
|
|
|
|
Some systems
|
|
|
|
.\" e.g., Solaris 8
|
|
|
|
use the first white space to terminate
|
|
|
|
.IR optional-arg .
|
|
|
|
On some systems,
|
|
|
|
.\" e.g., FreeBSD before 6.0, but not FreeBSD 6.0 onward
|
|
|
|
an interpreter script can have multiple arguments,
|
|
|
|
and white spaces in
|
|
|
|
.I optional-arg
|
|
|
|
are used to delimit the arguments.
|
|
|
|
|
|
|
|
Linux ignores the set-user-ID and set-group-ID bits on scripts.
|
|
|
|
.\"
|
2014-05-14 14:05:34 +00:00
|
|
|
.\" .SH BUGS
|
|
|
|
.\" Some Linux versions have failed to check permissions on ELF
|
|
|
|
.\" interpreters. This is a security hole, because it allows users to
|
|
|
|
.\" open any file, such as a rewinding tape device, for reading. Some
|
|
|
|
.\" Linux versions have also had other security holes in
|
|
|
|
.\" .BR execve ()
|
|
|
|
.\" that could be exploited for denial of service by a suitably crafted
|
|
|
|
.\" ELF binary. There are no known problems with 2.0.34 or 2.2.15.
|
|
|
|
.SS execve() and EAGAIN
|
|
|
|
A more detailed explanation of the
|
|
|
|
.BR EAGAIN
|
|
|
|
error that can occur (since Linux 3.1) when calling
|
|
|
|
.BR execve ()
|
|
|
|
is as follows.
|
|
|
|
|
|
|
|
The
|
|
|
|
.BR EAGAIN
|
|
|
|
error can occur when a
|
|
|
|
.I preceding
|
|
|
|
call to
|
|
|
|
.BR setuid (2),
|
|
|
|
.BR setreuid (2),
|
|
|
|
or
|
|
|
|
.BR setresuid (2)
|
|
|
|
caused the real user ID of the process to change,
|
|
|
|
and that change caused the process to exceed its
|
|
|
|
.BR RLIMIT_NPROC
|
|
|
|
resource limit (i.e., the number of processes belonging
|
|
|
|
to the new real UID exceeds the resource limit).
|
2014-05-22 13:24:55 +00:00
|
|
|
From Linux 2.6.0 to 3.0, this caused the
|
2014-05-14 14:05:34 +00:00
|
|
|
.BR set*uid ()
|
|
|
|
call to fail.
|
2014-05-22 13:24:55 +00:00
|
|
|
(Prior to 2.6,
|
|
|
|
.\" commit 909cc4ae86f3380152a18e2a3c44523893ee11c4
|
|
|
|
the resource limit was not imposed on processes that
|
|
|
|
changed their user IDs.)
|
2014-05-14 14:05:34 +00:00
|
|
|
|
|
|
|
Since Linux 3.1, the scenario just described no longer causes the
|
|
|
|
.BR set*uid ()
|
|
|
|
call to fail,
|
|
|
|
because it too often led to security holes where buggy applications
|
|
|
|
didn't check the return status and assumed
|
|
|
|
that\(emif the caller had root privileges\(emthe call would always succeed.
|
|
|
|
Instead, the
|
|
|
|
.BR set*uid ()
|
|
|
|
calls now successfully change the real UID,
|
|
|
|
but the kernel sets an internal flag, named
|
|
|
|
.BR PF_NPROC_EXCEEDED ,
|
|
|
|
to note that the
|
|
|
|
.BR RLIMIT_NPROC
|
|
|
|
resource limit has been exceeded.
|
2014-05-27 04:51:02 +00:00
|
|
|
If the
|
|
|
|
.BR PF_NPROC_EXCEEDED
|
|
|
|
flag is set and the resource limit is still
|
|
|
|
exceeded at the time of a subsequent
|
2014-05-14 14:05:34 +00:00
|
|
|
.BR execve ()
|
|
|
|
call, that call fails with the error
|
|
|
|
.BR EAGAIN .
|
|
|
|
This kernel logic ensures that the
|
|
|
|
.BR RLIMIT_NPROC
|
|
|
|
resource limit is still enforced for the
|
|
|
|
common privileged daemon workflow\(emnamely,
|
|
|
|
.BR fork (2)
|
|
|
|
+
|
|
|
|
.BR set*uid ()
|
|
|
|
+
|
|
|
|
.BR execve ().
|
|
|
|
|
|
|
|
If the resource limit was not still exceeded at the time of the
|
|
|
|
.BR execve ()
|
|
|
|
call
|
|
|
|
(because other processes belonging to this real UID terminated between the
|
2015-01-16 06:55:01 +00:00
|
|
|
.BR set*uid ()
|
2014-05-14 14:05:34 +00:00
|
|
|
call and the
|
|
|
|
.BR execve ()
|
|
|
|
call), then the
|
|
|
|
.BR execve ()
|
|
|
|
call succeeds and the kernel clears the
|
|
|
|
.BR PF_NPROC_EXCEEDED
|
|
|
|
process flag.
|
|
|
|
The flag is also cleared if a subsequent call to
|
|
|
|
.BR fork (2)
|
|
|
|
by this process succeeds.
|
2007-05-16 02:45:55 +00:00
|
|
|
.SS Historical
|
2014-05-07 01:09:57 +00:00
|
|
|
With UNIX\ V6, the argument list of an
|
2005-10-20 15:11:10 +00:00
|
|
|
.BR exec ()
|
|
|
|
call was ended by 0,
|
2004-11-03 13:51:07 +00:00
|
|
|
while the argument list of
|
|
|
|
.I main
|
2007-06-08 03:17:37 +00:00
|
|
|
was ended by \-1.
|
|
|
|
Thus, this argument list was not directly usable in a further
|
2007-04-12 22:42:49 +00:00
|
|
|
.BR exec ()
|
2005-10-20 15:11:10 +00:00
|
|
|
call.
|
2014-05-07 01:09:57 +00:00
|
|
|
Since UNIX\ V7, both are NULL.
|
2014-05-15 12:57:03 +00:00
|
|
|
.\"
|
|
|
|
.\" .SH BUGS
|
|
|
|
.\" Some Linux versions have failed to check permissions on ELF
|
|
|
|
.\" interpreters. This is a security hole, because it allows users to
|
|
|
|
.\" open any file, such as a rewinding tape device, for reading. Some
|
|
|
|
.\" Linux versions have also had other security holes in
|
|
|
|
.\" .BR execve ()
|
|
|
|
.\" that could be exploited for denial of service by a suitably crafted
|
|
|
|
.\" ELF binary. There are no known problems with 2.0.34 or 2.2.15.
|
2007-04-30 12:25:52 +00:00
|
|
|
.SH EXAMPLE
|
2008-08-07 11:08:15 +00:00
|
|
|
The following program is designed to be execed by the second program below.
|
2014-04-20 04:32:43 +00:00
|
|
|
It just echoes its command-line arguments, one per line.
|
2007-04-30 12:25:52 +00:00
|
|
|
|
2007-12-19 06:57:44 +00:00
|
|
|
.in +4n
|
2007-04-30 12:25:52 +00:00
|
|
|
.nf
|
|
|
|
/* myecho.c */
|
|
|
|
|
|
|
|
#include <stdio.h>
|
|
|
|
#include <stdlib.h>
|
|
|
|
|
|
|
|
int
|
|
|
|
main(int argc, char *argv[])
|
|
|
|
{
|
|
|
|
int j;
|
|
|
|
|
|
|
|
for (j = 0; j < argc; j++)
|
|
|
|
printf("argv[%d]: %s\\n", j, argv[j]);
|
|
|
|
|
|
|
|
exit(EXIT_SUCCESS);
|
|
|
|
}
|
|
|
|
.fi
|
|
|
|
.in
|
|
|
|
|
|
|
|
This program can be used to exec the program named in its command-line
|
|
|
|
argument:
|
2007-12-19 06:57:44 +00:00
|
|
|
.in +4n
|
2007-04-30 12:25:52 +00:00
|
|
|
.nf
|
|
|
|
|
|
|
|
/* execve.c */
|
|
|
|
|
|
|
|
#include <stdio.h>
|
|
|
|
#include <stdlib.h>
|
|
|
|
#include <unistd.h>
|
|
|
|
|
|
|
|
int
|
|
|
|
main(int argc, char *argv[])
|
|
|
|
{
|
|
|
|
char *newargv[] = { NULL, "hello", "world", NULL };
|
|
|
|
char *newenviron[] = { NULL };
|
|
|
|
|
execve.2, pipe.2, tee.2, fmemopen.3, mq_notify.3, qsort.3: Replace use of assert() by code that checks argc
See http://bugzilla.kernel.org/show_bug.cgi?id=13569
As noted by Andrey:
The purpose of the assert macro, defined in <assert.h>,
is to provide a tool to check for programming mistakes
or program logic errors. However, the assert macro must
never be used to perform checks for run time errors,
since, with the NDEBUG macro defined, expressions within
the assert macro invocations are not evaluated/checked
for, resulting in behavior that was not originally intended.
...
The pages affected in the core package are
execve(2)
pipe(2)
tee(2)
fmemopen(3)
mq_notify(3)
qsort(3)
Reported-by: Andrey Vihrov <vihrov@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2009-09-15 04:46:16 +00:00
|
|
|
if (argc != 2) {
|
execve.2, get_robust_list.2, getunwind.2, pipe.2, quotactl.2, clock_getcpuclockid.3, endian.3, fmemopen.3, getgrouplist.3, getservent_r.3, mq_notify.3, qsort.3, rtime.3, mailaddr.7: ffix: replace tabs with white space in code examples
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2014-01-18 07:45:45 +00:00
|
|
|
fprintf(stderr, "Usage: %s <file\-to\-exec>\\n", argv[0]);
|
|
|
|
exit(EXIT_FAILURE);
|
execve.2, pipe.2, tee.2, fmemopen.3, mq_notify.3, qsort.3: Replace use of assert() by code that checks argc
See http://bugzilla.kernel.org/show_bug.cgi?id=13569
As noted by Andrey:
The purpose of the assert macro, defined in <assert.h>,
is to provide a tool to check for programming mistakes
or program logic errors. However, the assert macro must
never be used to perform checks for run time errors,
since, with the NDEBUG macro defined, expressions within
the assert macro invocations are not evaluated/checked
for, resulting in behavior that was not originally intended.
...
The pages affected in the core package are
execve(2)
pipe(2)
tee(2)
fmemopen(3)
mq_notify(3)
qsort(3)
Reported-by: Andrey Vihrov <vihrov@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2009-09-15 04:46:16 +00:00
|
|
|
}
|
|
|
|
|
2007-04-30 12:25:52 +00:00
|
|
|
newargv[0] = argv[1];
|
|
|
|
|
|
|
|
execve(argv[1], newargv, newenviron);
|
2015-01-28 09:14:53 +00:00
|
|
|
perror("execve"); /* execve() returns only on error */
|
2007-04-30 12:25:52 +00:00
|
|
|
exit(EXIT_FAILURE);
|
|
|
|
}
|
|
|
|
.fi
|
|
|
|
.in
|
|
|
|
|
|
|
|
We can use the second program to exec the first as follows:
|
|
|
|
|
2007-12-19 06:57:44 +00:00
|
|
|
.in +4n
|
2007-04-30 12:25:52 +00:00
|
|
|
.nf
|
eventfd.2, execve.2, getdents.2, ioprio_set.2, mprotect.2, signalfd.2, timerfd_create.2, wait.2, backtrace.3, clock_getcpuclockid.3, end.3, fmemopen.3, fopencookie.3, frexp.3, getdate.3, getgrouplist.3, getprotoent_r.3, getservent_r.3, gnu_get_libc_version.3, inet.3, inet_pton.3, makecontext.3, malloc.3, matherr.3, offsetof.3, pthread_attr_init.3, pthread_create.3, pthread_getattr_np.3, sem_wait.3, strftime.3, strtok.3, strtol.3, core.5, proc.5, cpuset.7, mq_overview.7: Global fix: Format user input in shell sessions in boldface
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2008-10-28 15:37:22 +00:00
|
|
|
.RB "$" " cc myecho.c \-o myecho"
|
|
|
|
.RB "$" " cc execve.c \-o execve"
|
|
|
|
.RB "$" " ./execve ./myecho"
|
2007-04-30 12:25:52 +00:00
|
|
|
argv[0]: ./myecho
|
|
|
|
argv[1]: hello
|
|
|
|
argv[2]: world
|
|
|
|
.fi
|
|
|
|
.in
|
|
|
|
|
|
|
|
We can also use these programs to demonstrate the use of a script
|
|
|
|
interpreter.
|
|
|
|
To do this we create a script whose "interpreter" is our
|
|
|
|
.I myecho
|
|
|
|
program:
|
|
|
|
|
2007-12-19 06:57:44 +00:00
|
|
|
.in +4n
|
2007-04-30 12:25:52 +00:00
|
|
|
.nf
|
execve.2: Remove unneeded ".sh" extension in interpreter script example
See https://bugzilla.kernel.org/show_bug.cgi?id=84701
As noted by C. Alex North-Keys:
1) Command name extensions considered harmful: Adding ".sh", or
any other unneeded extension, unnecessarily duplicates meta
information already present in the interpreter directive,
exposing an implementation detail that then ends up explicitly
part of other programs running this one. Later, when such a
script is replaced with a new version in Python, C, etc., the
useless ".sh" has to be retained to avoid breaking those other
programs' calls to this one, and now has a stark antifunction
of lying about the script's content and occasionally causing
admins to run undefined experiments as root (like
"bash -x ./reallyperlscript.sh"). Such extensions, while fine
in DOS which ignores extensions explicitly, is a serious flaw
in Unix-targeted script writing. Canonical documentation
from the Linux manual should not support such a flawed idiom -
recommending against it would be preferred.
A more extensive rant against them can be found at:
http://www.talisman.org/~erlkonig/documents/commandname-extensions-considered-harmful
2) The space after "#!" in the interpreter directive is minor -
and the kernel's fs/binfmt_script.c specifically allows for it -
but versions of unix have length limits from ~30 characters to
Linux's 127 or so (if that number's correct) so the space does
have a cost. Most scripts I've seen lack that space, and
there's no real reason to encourage it.
Reported-by: C. Alex North-Keys <erlkonig@talisman.org>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2014-09-23 04:09:41 +00:00
|
|
|
.RB "$" " cat > script"
|
|
|
|
.B #!./myecho script-arg
|
eventfd.2, execve.2, getdents.2, ioprio_set.2, mprotect.2, signalfd.2, timerfd_create.2, wait.2, backtrace.3, clock_getcpuclockid.3, end.3, fmemopen.3, fopencookie.3, frexp.3, getdate.3, getgrouplist.3, getprotoent_r.3, getservent_r.3, gnu_get_libc_version.3, inet.3, inet_pton.3, makecontext.3, malloc.3, matherr.3, offsetof.3, pthread_attr_init.3, pthread_create.3, pthread_getattr_np.3, sem_wait.3, strftime.3, strtok.3, strtol.3, core.5, proc.5, cpuset.7, mq_overview.7: Global fix: Format user input in shell sessions in boldface
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2008-10-28 15:37:22 +00:00
|
|
|
.B ^D
|
execve.2: Remove unneeded ".sh" extension in interpreter script example
See https://bugzilla.kernel.org/show_bug.cgi?id=84701
As noted by C. Alex North-Keys:
1) Command name extensions considered harmful: Adding ".sh", or
any other unneeded extension, unnecessarily duplicates meta
information already present in the interpreter directive,
exposing an implementation detail that then ends up explicitly
part of other programs running this one. Later, when such a
script is replaced with a new version in Python, C, etc., the
useless ".sh" has to be retained to avoid breaking those other
programs' calls to this one, and now has a stark antifunction
of lying about the script's content and occasionally causing
admins to run undefined experiments as root (like
"bash -x ./reallyperlscript.sh"). Such extensions, while fine
in DOS which ignores extensions explicitly, is a serious flaw
in Unix-targeted script writing. Canonical documentation
from the Linux manual should not support such a flawed idiom -
recommending against it would be preferred.
A more extensive rant against them can be found at:
http://www.talisman.org/~erlkonig/documents/commandname-extensions-considered-harmful
2) The space after "#!" in the interpreter directive is minor -
and the kernel's fs/binfmt_script.c specifically allows for it -
but versions of unix have length limits from ~30 characters to
Linux's 127 or so (if that number's correct) so the space does
have a cost. Most scripts I've seen lack that space, and
there's no real reason to encourage it.
Reported-by: C. Alex North-Keys <erlkonig@talisman.org>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2014-09-23 04:09:41 +00:00
|
|
|
.RB "$" " chmod +x script"
|
2007-04-30 12:25:52 +00:00
|
|
|
.fi
|
|
|
|
.in
|
|
|
|
|
|
|
|
We can then use our program to exec the script:
|
|
|
|
|
2007-12-19 06:57:44 +00:00
|
|
|
.in +4n
|
2007-04-30 12:25:52 +00:00
|
|
|
.nf
|
execve.2: Remove unneeded ".sh" extension in interpreter script example
See https://bugzilla.kernel.org/show_bug.cgi?id=84701
As noted by C. Alex North-Keys:
1) Command name extensions considered harmful: Adding ".sh", or
any other unneeded extension, unnecessarily duplicates meta
information already present in the interpreter directive,
exposing an implementation detail that then ends up explicitly
part of other programs running this one. Later, when such a
script is replaced with a new version in Python, C, etc., the
useless ".sh" has to be retained to avoid breaking those other
programs' calls to this one, and now has a stark antifunction
of lying about the script's content and occasionally causing
admins to run undefined experiments as root (like
"bash -x ./reallyperlscript.sh"). Such extensions, while fine
in DOS which ignores extensions explicitly, is a serious flaw
in Unix-targeted script writing. Canonical documentation
from the Linux manual should not support such a flawed idiom -
recommending against it would be preferred.
A more extensive rant against them can be found at:
http://www.talisman.org/~erlkonig/documents/commandname-extensions-considered-harmful
2) The space after "#!" in the interpreter directive is minor -
and the kernel's fs/binfmt_script.c specifically allows for it -
but versions of unix have length limits from ~30 characters to
Linux's 127 or so (if that number's correct) so the space does
have a cost. Most scripts I've seen lack that space, and
there's no real reason to encourage it.
Reported-by: C. Alex North-Keys <erlkonig@talisman.org>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2014-09-23 04:09:41 +00:00
|
|
|
.RB "$" " ./execve ./script"
|
2007-04-30 12:25:52 +00:00
|
|
|
argv[0]: ./myecho
|
|
|
|
argv[1]: script-arg
|
execve.2: Remove unneeded ".sh" extension in interpreter script example
See https://bugzilla.kernel.org/show_bug.cgi?id=84701
As noted by C. Alex North-Keys:
1) Command name extensions considered harmful: Adding ".sh", or
any other unneeded extension, unnecessarily duplicates meta
information already present in the interpreter directive,
exposing an implementation detail that then ends up explicitly
part of other programs running this one. Later, when such a
script is replaced with a new version in Python, C, etc., the
useless ".sh" has to be retained to avoid breaking those other
programs' calls to this one, and now has a stark antifunction
of lying about the script's content and occasionally causing
admins to run undefined experiments as root (like
"bash -x ./reallyperlscript.sh"). Such extensions, while fine
in DOS which ignores extensions explicitly, is a serious flaw
in Unix-targeted script writing. Canonical documentation
from the Linux manual should not support such a flawed idiom -
recommending against it would be preferred.
A more extensive rant against them can be found at:
http://www.talisman.org/~erlkonig/documents/commandname-extensions-considered-harmful
2) The space after "#!" in the interpreter directive is minor -
and the kernel's fs/binfmt_script.c specifically allows for it -
but versions of unix have length limits from ~30 characters to
Linux's 127 or so (if that number's correct) so the space does
have a cost. Most scripts I've seen lack that space, and
there's no real reason to encourage it.
Reported-by: C. Alex North-Keys <erlkonig@talisman.org>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2014-09-23 04:09:41 +00:00
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argv[2]: ./script
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2007-04-30 12:25:52 +00:00
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argv[3]: hello
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argv[4]: world
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.fi
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.in
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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
|
2004-11-03 13:51:07 +00:00
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|
|
.BR chmod (2),
|
2015-01-09 13:25:05 +00:00
|
|
|
.BR execveat (2),
|
2004-11-03 13:51:07 +00:00
|
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|
.BR fork (2),
|
Hi Andries,
> The question came up whether execve of a suid binary while being ptraced
> would fail or ignore the suid part. The answer today seems to be the
> latter:
>
> E.g. (in 2.6.11) security/dummy.c:
>
> static void dummy_bprm_apply_creds (struct linux_binprm *bprm, int
> unsafe)
> {
> if (bprm->e_uid != current->uid || bprm->e_gid != current->gid) {
> if ((unsafe & ~LSM_UNSAFE_PTRACE_CAP) &&
> !capable(CAP_SETUID)) {
> bprm->e_uid = current->uid;
> bprm->e_gid = current->gid;
> }
> }
> }
>
> and fs/exec.c:
>
> void compute_creds(struct linux_binprm *bprm) {
> int unsafe;
>
> unsafe = unsafe_exec(current);
> security_bprm_apply_creds(bprm, unsafe);
> }
>
> static inline int unsafe_exec(struct task_struct *p) {
> int unsafe = 0;
> if (p->ptrace & PT_PTRACED) {
> if (p->ptrace & PT_PTRACE_CAP)
> unsafe |= LSM_UNSAFE_PTRACE_CAP;
> else
> unsafe |= LSM_UNSAFE_PTRACE;
> }
> return unsafe;
> }
>
> That is: if the process that calls execve() is being traced,
> the LSM_UNSAFE_PTRACE bit is et in unsafe and security_bprm_apply_creds()
> will make sure the suid/sgid bits are ignored.
>
> ---
>
> In my man page I do not read anything like that. It says
>
> EPERM The process is being traced, the user is not the superuser and
> the file has an SUID or SGID bit set.
> and
>
> If the current program is being ptraced, a SIGTRAP is sent to it after
> a successful execve().
>
> If the set-uid bit is set on the program file pointed to by filename
> the effective user ID of the calling process is changed to that of the
> owner of the program file.
>
> So, maybe this sentence should be amended to read
>
> If the set-uid bit is set on the program file pointed to by filename
> and the current process is not being ptraced, the effective user ID
> of the calling process is changed to ...
I changed your "current" to "calling" (to be consistent with the
rest of the page), but otherwise applied as you suggest.
The revision will appear in man-pages-2.03, which I can release
any time now. Are you avialable to do an upload tomorrow?
2005-05-31 16:07:24 +00:00
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.BR ptrace (2),
|
2004-11-03 13:51:07 +00:00
|
|
|
.BR execl (3),
|
2006-03-07 02:20:16 +00:00
|
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.BR fexecve (3),
|
2007-09-10 04:31:59 +00:00
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.BR getopt (3),
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2007-06-08 07:57:18 +00:00
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.BR credentials (7),
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2008-07-14 15:52:21 +00:00
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.BR environ (7),
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2007-05-26 12:41:39 +00:00
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.BR path_resolution (7),
|
2004-11-03 13:51:07 +00:00
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.BR ld.so (8)
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