man-pages-5.05 is released

I've released man-pages-5.05. The release tarball is available on kernel.org. The browsable online pages can be found on man7.org. The Git repository for man-pages is available on kernel.org.

This release resulted from patches, bug reports, reviews, and comments from more than 40 contributors. The release includes approximately 110 commits that change around 50 pages.

man-pages-5.04 is released

I've released man-pages-5.04. The release tarball is available on kernel.org. The browsable online pages can be found on man7.org. The Git repository for man-pages is available on kernel.org.

This release resulted from patches, bug reports, reviews, and comments from 15 contributors. The release includes approximately 80 commits that change just under 30 pages.

The most notable of the changes in man-pages-5.04 are the following:

• With some help from Christian Brauner, I've added documentation of the clone3() system call (new in Linux 5.3) to the clone(2) manual page. In addition, several other parts of the clone(2) manual page were cleaned up and reworked.
• I've refreshed the the bpf-helpers(7) page against the latest kernel sources; as a result, the page has grown size by about 25%.

Another small but important change is the addition of documentation of the P_PIDFD idtype in the waitid(2) manual page. This feature, added in Linux 5.4, allows a parent process to wait on a child process that is referred to by a PID file descriptor, and constitutes the final cornerstone in the pidfd API.

man-pages-5.03 is released

I've released man-pages-5.03. The release tarball is available on kernel.org. The browsable online pages can be found on man7.org. The Git repository for man-pages is available on kernel.org.

This release resulted from patches, bug reports, reviews, and comments from 45 contributors. The release includes over 200 commits that change around 80 pages.

The most notable of the changes in man-pages-5.03 are the following:

• I've written a new pidfd_send_signal(2) page that documents the system call  of the same name. This system call, which was added in Linux 5.1, makes it possible to send a signal to a process referred to via a file descriptor. This allows the avoidance of race conditions that can occur using traditional APIs (e.g., kill(2)) to signal a process, which may result in signaling the wrong process if the intended target process has already terminated and its PID has been recycled.
• I've written a new pidfd_open(2) page that documents the system call  of the same name. This system call, which was added in Linux 5.3, can be used to obtain a file descriptor for a process with a specified PID. This file descriptor can be used as argument to pidfd_send_signal(). Soon (Linux 5.4), it will also be  possible to use this file descriptor to wait for the process using waitid(2).
• I've completely rewritten the pivot_root(2) manual page, adding a lot of missing details (including the use of pivot_root(".", ".")) and an example program.  In addition, the text prevaricating on whether or not pivot_root() might change the root and current working directories has been eliminated, and replaced with a simple description of the behavior of the system call, which has not changed for 19 years, and will not change in the future.  Many longstanding errors in the old version of the page have also been corrected.
• Christian Brauner added documentation of the CLONE_PIDFD flag to the clone(2) manual page.  This flag (added in Linux 5.2) can be used to obtain a file descriptor that refers to the child process created by clone(2). This file descriptor can be used for the same purposes as the file descriptor returned by pidfd_open(2).
• Dmitry Levin as added documentation of a new option, PTRACE_GET_SYSCALL_INFO, to the ptrace(2) manual page.
• Two new pages, ipc_namespaces(7) and uts_namespaces(7), have been created by splitting out content that was formerly part of the namespaces(7) page.

man-pages-5.02 is released

I've released man-pages-5.02. The release tarball is available on kernel.org. The browsable online pages can be found on man7.org. The Git repository for man-pages is available on kernel.org.

This release resulted from patches, bug reports, reviews, and comments from 28 contributors. The release includes around 120 commits that change more than 50 pages.

The most notable of the changes in man-pages-5.02 is the following:

• Thanks to Matthew Bobrowski, extensive documentation of FAN_REPORT_FID and directory modification events has been added to the fanotify(7), fanotify_init(2), and fanotify_mark(2) pages.
• I have added several details on the dlopen API to the dlopen(3) page.
• I've corrected a few longstanding errors and omissions in the pivot_root(2) manual page, and much more extensive changes for this page are in the pipeline for the next release.

man-pages-5.01 is released

I've released man-pages-5.01. The release tarball is available on kernel.org. The browsable online pages can be found on man7.org. The Git repository for man-pages is available on kernel.org.

This release resulted from patches, bug reports, reviews, and comments from just over 20 contributors. The release is smaller release than typical; it includes just over 70 commits that changed just over 40 pages.

The most notable of the changes in man-pages-5.01 is the following:

• The tsearch(3) page adds documentation of the new twalk_r() function that is added in the upcoming glibc 2.30 release. Thanks to Florian Weimer.

man-pages-5.00 is released

I've released man-pages-5.00. The release tarball is available on kernel.org. The browsable online pages can be found on man7.org. The Git repository for man-pages is available on kernel.org.

This release resulted from patches, bug reports, reviews, and comments from around 130 contributors. The release is rather larger than average, since it has been nearly a year since the last release. The release includes more than 600 commits that changed nearly 400 pages. In addition, 3 new manual pages were added.

Among the more significant changes in man-pages-5.,00 are the following:

• A new page, bpf-helpers(7), documents the helper functions that the kernel provide for eBPF programs to call. This page is autogenerated from kernel files, and was brought to life in the man-pages project by Quentin Monnet.
• Various updates to the perf_event_open(2) page by Vince Weaver.
• A new s390_guarded_storage(2) page by Eugene Syromyatnikov documents the s390-specific system call of the same name.
• The addition of many formerly absent architecture-specific system calls in the table of system calls shown syscalls(2).
• A significant overhaul of the lirc4) page by Sean Young.
• Many additions to the proc(5) page.
• Much of the detail on socket address families in the rather overloaded socket(2) page has now been moved to a new address_families(7) page.
• A large number of additions, mostly by me, in the capabilities(7) page.
• Many improvements, all by me, in the discussion of ancillary data in the unix(7) page.

In addition, two pages have been removed in this release after encouragement from Ingo Schwarze: mdoc(7) and mdoc.samples(7). As the commit message notes, groff_mdoc(7) from the groff project provides a better equivalent of mdoc.samples(7) and the mandoc project provides a better mdoc(7). And nowadays, there are virtually no pages in man-pages that use mdoc markup.

Again special thanks to Eugene Syromyatnikov, who contributed nearly 30 patches to this release!

man-pages-4.16 is released

I've released man-pages-4.16. The release tarball is available on kernel.org. The browsable online pages can be found on man7.org. The Git repository for man-pages is available on kernel.org.

This release resulted from patches, bug reports, reviews, and comments from 29 contributors. Somewhat more than 160 commits changed around 60 pages. A summary of the changes can be found here.

man-pages-4.15 is released

I've released man-pages-4.15. The release tarball is available on kernel.org. The browsable online pages can be found on man7.org. The Git repository for man-pages is available on kernel.org.

This release resulted from patches, bug reports, reviews, and comments from 26 contributors. Just over 200 commits changed around 75 pages. In addition, 3 new manual pages were added.

Among the more significant changes in man-pages-4.15 are the following:

• A new vsock(7) page, written by Stefan Hajnoczi, documents the the VSOCK socket address family.
• A new network_namespaces(7) page, based on content moved from the existing namespaces(7) page with a few additions, documents network namespaces.
• A new s390_sthyi(2) page, written by QingFeng Hao, documents the s390 specific system call of the same name.
• With some help from Tejun Heo and Roman Gushchin, I've substantially enhanced the cgroups(7) page. The page has more than doubled in size and among many other changes, it now contains a description of the "thread mode" feature added in Linux 4.14.

Next Linux/UNIX System Programming course in Munich, 5-9 February, 2018

There are still some places free for my next 5-day Linux/UNIX System Programming course to take place in Munich, Germany, for the week of 5-9 February 2018.

The course is intended for programmers developing system-level, embedded, or network applications for Linux and UNIX systems, or programmers porting such applications from other operating systems (e.g., proprietary embedded/realtime operaring systems or Windows) to Linux or UNIX. The course is based on my book, The Linux Programming Interface (TLPI), and covers topics such as low-level file I/O; signals and timers; creating processes and executing programs; POSIX threads programming; interprocess communication (pipes, FIFOs, message queues, semaphores, shared memory), and network programming (sockets).
     
The course has a lecture+lab format, and devotes substantial time to working on some carefully chosen programming exercises that put the "theory" into practice. Students receive printed and electronic copies of TLPI, along with a 600-page course book that includes all slides presented in the course. A reading knowledge of C is assumed; no previous system programming experience is needed.

Some useful links for anyone interested in the course:

• course overview (includes sample course materials, course dates and locations, and prices); 
• course topic list; and 
• information about the trainer (i.e., me).
• 2-page PDF containing key information about the course

Questions about the course? Email me via training@man7.org.

man-pages-4.14 is released

I've released man-pages-4.14. The release tarball is available on kernel.org. The browsable online pages can be found on man7.org. The Git repository for man-pages is available on kernel.org.

This release resulted from patches, bug reports, reviews, and comments from 71 contributors. Nearly 400 commits changed more than 160 pages. In addition, 4 new manual pages were added.

Among the more significant changes in man-pages-4.14 are the following:

• With help from several people, I've added a new pthread_spin_init(3) page describing pthread_spin_init() and pthread_spin_destroy(). This page provides some recommendations on when the usage of spin locks is appropriate.
• I added a new pthread_spin_lock(3) page describing pthread_spin_lock(), pthread_spin_unlock(), and pthread_spin_trylock().
• A new smartpqi(4) page, written by Don Brace, documents the smartpqi SCSI controller.
• A new veth(4) page, written by Tomáš Pospíšek, Eric Biederman, and me, documents veth virtual ethernet devices.
• Substantial additions were made to the seccomp(2) page, by Tyler Hicks and me, documenting the many new seccomp features added in the Linux 4.14 kernel. In addition, I've added a section noting various caveats regarding the use of seccomp. (See also the LWN.net article, The inherent fragility of seccomp(), which is accompanied by a number of quite informative comments.)

man-pages-4.13 is released

I've released man-pages-4.13. The release tarball is available on kernel.org. The browsable online pages can be found on man7.org. The Git repository for man-pages is available on kernel.org.

This release resulted from patches, bug reports, reviews, and comments from around 40 contributors. The release is rather larger than average. (The context diff runs to more than 90k lines.) The release includes more than 350 commits and contains some fairly wide-ranging formatting fix-ups that meant that all 1028 existing manual pages saw some change(s). In addition, 5 new manual pages were added.

Among the more significant changes in man-pages-4.13 are the following:

• Two new pages, pthread_mutexattr_setrobust(3) and pthread_mutex_consistent(3) cowritten by Yubin Ruan and myself, document the POSIX threads APIs related to robust mutexes (pthread_mutexattr_setrobust(), pthread_mutexattr_getrobust(), and pthread_mutex_consistent()). In conjunction with those chganges, I also added some further details on the underlying robust futexes implementation to the get_robust_list(2) manual page.
• I've written a new page, pthread_mutexattr_init(3), that documents pthread_mutexattr_init() and pthread_mutexattr_destroy() functions.
• I've written a new page, pthread_mutexattr_getpshared(3), that documents pthread_mutexattr_getpshared() and pthread_mutexattr_setpshared() functions.
• At long last, I've added a sysfs(5) man page to start documenting the sysfs filesystem. This page does not yet contain details on many sysfs files, but hopefully that may change in the future, if people send me patches for the page.

A special thanks to Eugene Syromyatnikov, who contributed 30 patches to this release!

man-pages-4.12 is released

I've released man-pages-4.12. The release tarball is available on kernel.org. The browsable online pages can be found on man7.org. The Git repository for man-pages is available on kernel.org.

This release resulted from patches, bug reports, reviews, and comments from around 30 contributors. It includes just under 200 commits changing around 90 pages. This is a relatively small release, with one new manual page, ioctl_getfsmap(2). The most significant change in the release consists of a number of additions and improvements in the ld.so(8) page.

Linux Shared Libraries course, Munich, Germany, 20 July 2017

I've scheduled a public instance of my "Building and Using Shared Libraries on Linux" course to take place in Munich, Germany on 20 July 2017.  This one-day course provides a thorough introduction to building and using shared libraries. covering topics such as: the basics of creating, installing, and using shared libraries; shared library versioning and naming conventions; the role of the dynamic linker; run-time symbol resolution; controlling symbol visibility; symbol versioning; preloading shared libraries; and dynamically loaded libraries (dlopen). The course format is a mixture of theory and practical.

The course is aimed at programmers who create and use shared libraries. Systems administrators who are managing and troubleshooting applications that use shared libraries will also find the course useful.

You can find out more about the course (such as expected background and course pricing) at http://man7.org/training/shlib/ and see a detailed course outline at
http://man7.org/training/shlib/shlib_course_outline.html.

Cgroups/namespaces/seccomp/capabilities course

There are still some places available on my "Linux Security and Isolation APIs" that will take place in Munich, Germany on 17-19 July 2017.  This three-day course provides a deep understanding of the low-level Linux features (set-UID/set-GID programs, capabilities, namespaces, cgroups, and seccomp) used to implement privileged applications and build container, virtualization, and sandboxing technologies. The course format is a mixture of theory and practical.

The course is aimed at designers and programmers building privileged applications, container applications, and sandboxing applications. Systems administrators who are managing such applications are also likely to find the course of benefit.

You can find out more about the course (such as expected background and course pricing) at
http://man7.org/training/sec_isol_apis/
and see a detailed course outline at
http://man7.org/training/sec_isol_apis/sec_isol_apis_course_outline.html

man-pages-4.11 is released

I've released man-pages-4.11. The release tarball is available on kernel.org. The browsable online pages can be found on man7.org. The Git repository for man-pages is available on kernel.org.

This release resulted from patches, bug reports, reviews, and comments from over 30 contributors. It includes more than 300 commits changing over 100 pages. The changes include the addition of 5 pages, significant rewriting of 1 other page, and enhancements to many other pages.

Among the more significant changes in man-pages-4.11 are the following:

• Two new pages, userfaultfd(2) and ioctl_userfaultfd(2), written by me and Mike Rapoport, document the userfaultfd() system call that was added in Linux 4.3, along with associated ioctl() operations that can be performed on the file descriptor returned by that system call.
• A new statx(2) man page, written by David Howells, documents the statx() system call that was added in the just-released Linux 4.11 kernel.
• A new pthread_atfork(3) manual page documents the pthread_atfork() library function.
• The slabinfo(5) has been heavily updated to reflect current kernel details.