man-pages-5.02 is released

From: Michael Kerrisk (man-pages)
Date: Fri Aug 02 2019 - 06:18:19 EST


Gidday,

The Linux man-pages maintainer proudly announces:

man-pages-5.02 - man pages for Linux

This release resulted from patches, bug reports, reviews, and
comments from 28 people, with around 120 commits making changes
to over 50 pages.

Tarball download:
http://www.kernel.org/doc/man-pages/download.html
Git repository:
https://git.kernel.org/cgit/docs/man-pages/man-pages.git/
Online changelog:
http://man7.org/linux/man-pages/changelog.html#release_5.02

A short summary of the release is blogged at:
https://linux-man-pages.blogspot.com/2019/08/man-pages-502-is-released.html

The current version of the pages is browsable at:
http://man7.org/linux/man-pages/

A selection of changes in this release that may be of interest
to readers of LKML is shown below.

Cheers,

Michael

==================== Changes in man-pages-5.02 ====================

Released: 2019-08-02, Munich


Newly documented interfaces in existing pages
---------------------------------------------

fanotify.7
fanotify_init.2
fanotify_mark.2
Matthew Bobrowski [Amir Goldstein, Jan Kara]
Document FAN_REPORT_FID and directory modification events

vdso.7
Tobias Klauser [Palmer Dabbelt]
Document vDSO for RISCV

Changes to individual pages
---------------------------

pldd.1
G. Branden Robinson [Michael Kerrisk]
Document glibc's unbreakage of tool
After a longstanding breakage, pldd now works again (glibc 2.30).

execve.2
Michael Kerrisk [Eugene Syromyatnikov]
Since Linux 5.1, the limit on the #! line is 255 chars (rather than 127)

mprotect.2
Mark Wielaard
pkey_mprotect() acts like mprotect() if pkey is set to -1, not 0

pivot_root.2
Michael Kerrisk
ERRORS: EINVAL occurs if 'new_root' or its parent has shared propagation
Michael Kerrisk
'new_root' must be a mount point
It appears that 'new_root' may not have needed to be a mount
point on ancient kernels, but already in Linux 2.4.5 this changed.
Michael Kerrisk
'put_old' can't be a mount point with MS_SHARED propagation

tkill.2
Michael Kerrisk
glibc 2.30 provides a wrapper for tgkill()

dlopen.3
Michael Kerrisk
Clarify the rules for symbol resolution in a dlopen'ed object
The existing text wrongly implied that symbol look up first
occurred in the object and then in main, and did not mention
whether dependencies of main where used for symbol resolution.
Michael Kerrisk
Clarify when an executable's symbols can be used for symbol resolution
The --export-dynamic linker option is not the only way that main's
global symbols may end up in the dynamic symbol table and thus be
used to satisfy symbol reference in a shared object. A symbol
may also be placed into the dynamic symbol table if ld(1)
notices a dependency in another object during the static link.
Michael Kerrisk
An object opened with RTLD_LOCAL can be promoted to RTLD_GLOBAL
Michael Kerrisk
Note that symbol use might keep a dlclose'd object in memory
Michael Kerrisk
On dlclose(), destructors are called when reference count falls to 0
Michael Kerrisk
Make it clear that RTLD_NODELETE also affects global variables
Michael Kerrisk
Clarify that constructors are called only when library is first loaded

on_exit.3
Michael Kerrisk [Sami Kerola]
Stack variables may be out of scope when exit handler is invoked

capabilities.7
Michael Kerrisk
Add a note about using strace on binaries that have capabilities
Michael Kerrisk
Add pivot_root(2) to CAP_SYS_ADMIN list
Michael Kerrisk
CAP_FOWNER also allows modifying user xattrs on sticky directories

mount_namespaces.7
Michael Kerrisk
Clarify implications for other NS if mount point is removed in one NS
If a mount point is deleted or renamed or removed in one mount
namespace, this will cause an object that is mounted at that
location in another mount namespace to be unmounted (as verified
by experiment). This was implied by the existing text, but it is
better to make this detail explicit.
namespaces.7
Michael Kerrisk
Note initial values of hostname and domainname in a new UTS namespace

signal.7
Michal Sekletar [Oleg Nesterov, Michael Kerrisk]
Clarify that siginfo_t isn't changed on coalescing

unix.7
Michael Kerrisk
Note SCM_RIGHTS interaction with RLIMIT_NOFILE
If the file descriptors received in SCM_RIGHTS would cause
the process to its exceed RLIMIT_NOFILE limit, the excess
FDs are discarded.

user_namespaces.7
Michael Kerrisk
Describe the effect of file-related capabilities inside user namespaces
Michael Kerrisk
Describe how kernel treats UIDs/GIDs when a process accesses files

vdso.7
Tobias Klauser
Mention removal of Blackfin port in Linux 4.17

ld.so.8
Michael Kerrisk [Matthias Hertel]
Note some further details of secure-execution mode
Note some further details of the treatment of environment
variables in secure execution mode. In particular (as noted by
Matthias Hertel), note that ignored environment variables are also
stripped from the environment. Furthermore, there are some other
variables, not used by the dynamic linker itself, that are also
treated in this way (see the glibc source file
sysdeps/generic/unsecvars.h).

--
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
Linux/UNIX System Programming Training: http://man7.org/training/