==================== Changes in man-pages-5.08 ==================== Released: 2020-08-13, Munich Contributors ------------ The following people contributed patches/fixes or (noted in brackets in the changelog below) reports, notes, and ideas that have been incorporated in changes in this release: Alejandro Colomar Aleksa Sarai Alyssa Ross Andrew Price Andy Lutomirski Arkadiusz Drabczyk Benjamin Peterson Bjarni Ingi Gislason Bruno Haible Carlos O'Donell Catalin Marinas Dan Kenigsberg Dave Martin Diogo Miguel Ferreira Rodrigues Florian Weimer G. Branden Robinson Geoff Clare Helge Kreutzmann Jakub Wilk Jeff Layton John Scott Kumar Kartikeya Dwivedi Michael Kerrisk Mike Frysinger Oleksandr Kravchuk Philip Adams Rich Felker Saikiran Madugula Stephen Hemminger Sven Hoexter Thomas Bartelsmeier Thomas Piekarski victorm007@yahoo.com Apologies if I missed anyone! Newly documented interfaces in existing pages --------------------------------------------- prctl.2 Dave Martin Add SVE prctls (arm64) Add documentation for the the PR_SVE_SET_VL and PR_SVE_GET_VL prctls added in Linux 4.15 for arm64. Dave Martin [Catalin Marinas] Add tagged address ABI control prctls (arm64) Add documentation for the the PR_SET_TAGGED_ADDR_CTRL and PR_GET_TAGGED_ADDR_CTRL prctls added in Linux 5.4 for arm64. setns.2 Michael Kerrisk Document the use of PID file descriptors with setns() Starting with Linux 5.8, setns() can take a PID file descriptor as an argument, and move the caller into or more of the namespaces of the thread referred to by that descriptor. capabilities.7 Michael Kerrisk Document CAP_BPF Michael Kerrisk Add CAP_PERFMON symlink.7 Aleksa Sarai Document magic links more completely Global changes -------------- A few pages Michael Kerrisk Use \` rather than ` \` produces better rendering in PDF. Various pages Michael Kerrisk [Geoff Clare] Use "\(ti" instead of "~" A naked tilde ("~") renders poorly in PDF. Instead use "\(ti", which renders better in a PDF, and produces the same glyph when rendering on a terminal. Various pages Michael Kerrisk [Geoff Clare] Use "\(ha" rather than "^" in code This renders better in PDF. Various pages Mike Frysinger Drop "coding: UTF-8" header This header is used inconsistently -- man pages are UTF-8 encoded but not setting this marker. It's only respected by the man-db package, and seems a bit anachronistic at this point when UTF-8 is the standard default nowadays. Various pages Mike Frysinger Trim leading blank comment line Very few pages do this, so trim them. Various pages Mike Frysinger Use standard .\" comment style The \" comment produces blank lines. Use the .\" that the vast majority of the codebase uses instead. Various pages Mike Frysinger [G. Branden Robinson] Various pages: Drop t comment header Historically, a comment of the following form at the top of a manual page was used to indicate too man(1) that the use of tbl(1) was required in order to process tables: '\" t However, at least as far back as 2001 (according to Branden), man-db's man(1) automatically uses tbl(1) as needed, rendering this comment unnecessary. And indeed many existing pages in man-pages that have tables don't have this comment at the top of the file. So, drop the comment from those files where it is present. Changes to individual pages --------------------------- ioctl_tty.2 Michael Kerrisk Fix a confusing wording error in description of TIOCSPTLCK iopl.2 Thomas Piekarski [victorm007@yahoo.com] Updating description of permissions and disabling interrupts Update description of permissions for port-mapped I/O set per-thread and not per-process. Mention that iopl() can not disable interrupts since Linux 5.5 anymore and is in general deprecated and only provided for legacy X servers. See https://bugzilla.kernel.org/show_bug.cgi?id=205317 keyctl.2 Oleksandr Kravchuk Declare auth_key to fix a compilation error in example code lseek.2 Andrew Price List gfs2 support for SEEK_HOLE/SEEK_DATA mount.2 Michael Kerrisk ERRORS: add EINVAL for bind mount of mount namespace inode open.2 Michael Kerrisk Say a bit more about what happens when 'mode' is wrongly omitted pidfd_open.2 Michael Kerrisk Add the setns(2) use case for PID file descriptors Michael Kerrisk Close the pidfd in EXAMPLE Close the PID file descriptor in the example program, to hint to the reader that like every other kind of file descriptor, a PID FD should be closed. prctl.2 Michael Kerrisk The parent death signal is cleared on some credential changes See kernel/cred.c::commit_creds() in the Linux 5.6 source code. seccomp.2 Andy Lutomirski Improve x32 and nr truncation notes send.2 recv.2 Alyssa Ross Add msg_iovlen POSIX note msg_iovlen is incorrectly typed (according to POSIX) in addition to msg_controllen, but unlike msg_controllen, this wasn't mentioned for msg_iovlen. setns.2 Michael Kerrisk EXAMPLE: use O_CLOEXEC when opening namespace file descriptor Michael Kerrisk It is possible to setns() to the caller's current PID namespace The page currently incorrectly says that 'fd' must refer to a descendant PID namespace. However, 'fd' can also refer to the caller's current PID namespace. Verified by experiment, and also comments in kernel/pid_namespace.c (Linux 5.8-rc1). sync.2 Jeff Layton syncfs() now returns errors if writeback fails A patch has been merged for v5.8 that changes how syncfs() reports errors. Change the sync() manpage accordingly. syscalls.2 Michael Kerrisk Add faccessat2(), added in Linux 5.8 sysctl.2 Michael Kerrisk glibc removed support for sysctl() starting in version 2.32 atoi.3 Arkadiusz Drabczyk Explain disadvantages of atoi() Michael Kerrisk Relocate BUGS section Michael Kerrisk Add NOTES section explaining 0 return value on error And note that this is not specified by POSIX. fread.3 Arkadiusz Drabczyk Add example Arkadiusz Drabczyk Explain that file position is moved after calling fread()/fwrite() Corresponding manpage on FreeBSD already contains that information. getpt.3 posix_openpt.3 pts.4 Michael Kerrisk Use the term "pseudoterminal multiplexor device" for /dev/ptmx Let's use some consistent terminology for this device. posix_memalign.3 Bruno Haible Clarify how to free the result of posix_memalign pthread_rwlockattr_setkind_np.3 Carlos O'Donell [Kumar Kartikeya Dwivedi] Clarify a PTHREAD_RWLOCK_PREFER_WRITER_NP detail queue.3 Alejandro Colomar Remove wrong code from example Alejandro Colomar Comment out text for functions not in glibc (related: 6559169cac) pts.4 Michael Kerrisk Remove NOTES on BSD pseudoterminals This information is already covered better in pty(7). No need to mention it again here. hosts.5 Thomas Bartelsmeier Clarify capability for IPv6 outside of examples Resolves https://bugzilla.kernel.org/show_bug.cgi?id=208279 proc.5 Jakub Wilk Use "pwd -P" for printing cwd "/bin/pwd" happens to work with the GNU coreutils implementation, which has -P as the default, contrary to POSIX requirements. Use "pwd -P" instead, which is shorter, easier to type, and should work everywhere. Arkadiusz Drabczyk Inform that comm in /proc/pid/{stat,status} might also be truncated pgrep for example searches for a process name in /proc/pid/status resolv.conf.5 Michael Kerrisk [Helge Kreutzmann] Clarify that ip6-bytestring was removed in 2.25 capabilities.7 Dan Kenigsberg Clarify that CAP_SYS_NICE relates to *lowering* the nice value Saikiran Madugula CAP_SYS_RESOURCE: add two more items for POSIX message queues CAP_SYS_RESOURCE also allows overriding /proc/sys/fs/mqueue/msg_max and /proc/sys/fs/mqueue/msgsize_max. Michael Kerrisk [Dan Kenigsberg] Clarify wording around increasing process nice value Michael Kerrisk SEE ALSO: add getpcaps(8) cgroups.7 cpuset.7 Sven Hoexter Update kernel cgroup documentation references cgroups-v1/v2 documentation got moved to the "admin-guide" subfolder and converted from .txt files to .rst ip.7 Michael Kerrisk [Stephen Hemminger] Remove mention of ipfw(4) which was in long obsolete ipchains project man-pages.7 Michael Kerrisk Add some notes on generating optimal glyphs Getting nice renderings of ^ ` and ~ requires special steps in the page source. pty.7 Michael Kerrisk Explicitly mention CONFIG_LEGACY_PTYS Explicitly mention CONFIG_LEGACY_PTYS, and note that it is disabled by default since Linux 2.6.30. Michael Kerrisk Relocate a paragraph to NOTES standards.7 Michael Kerrisk Add an entry for POSIX.1-1988 Michael Kerrisk [Geoff Clare] Correct various details in the explanation of XPG/POSIX/SUS ld.so.8 Florian Weimer [Michael Kerrisk] List more places in which dynamic string tokens are expanded This happens for more than just DT_RPATH/DT_RUNPATH. Arkadiusz Drabczyk Explain that empty entry in LD_LIBRARY_PATH means cwd zic.8 Michael Kerrisk Sync to 2020a tzdb release From https://www.iana.org/time-zones, version 2020a.