Friday, October 11, 2019

man-pages-5.03 is released

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

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.