sigpause

SIGPAUSE(3)                Linux Programmer's Manual               SIGPAUSE(3)

NAME
       sigpause - atomically release blocked signals and wait for interrupt

SYNOPSIS
       #include <signal.h>

       int sigpause(int sigmask);  /* BSD (but see NOTES) */

       int sigpause(int sig);      /* System V / UNIX 95 */

DESCRIPTION
       Don't use this function.  Use sigsuspend(2) instead.

       The  function  sigpause()  is  designed  to  wait  for some signal.  It
       changes the process's signal mask (set of blocked  signals),  and  then
       waits  for  a signal to arrive.  Upon arrival of a signal, the original
       signal mask is restored.

RETURN VALUE
       If sigpause() returns, it was interrupted by a signal  and  the  return
       value is -1 with errno set to EINTR.

ATTRIBUTES
       For  an  explanation  of  the  terms  used  in  this  section,  see at-
       tributes(7).

       +-----------+---------------+---------+
       |Interface  | Attribute     | Value   |
       +-----------+---------------+---------+
       |sigpause() | Thread safety | MT-Safe |
       +-----------+---------------+---------+
CONFORMING TO
       The System V version of sigpause() is standardized in POSIX.1-2001.  It
       is also specified in POSIX.1-2008, where it is marked obsolete.

NOTES
   History
       The classical BSD version of this function appeared in 4.2BSD.  It sets
       the process's signal mask to sigmask.  UNIX 95 standardized the  incom-
       patible System V version of this function, which removes only the spec-
       ified signal sig from the process's signal mask.  The unfortunate situ-
       ation  with two incompatible functions with the same name was solved by
       the sigsuspend(2) function, that takes a sigset_t *  argument  (instead
       of an int).

   Linux notes
       On Linux, this routine is a system call only on the Sparc (sparc64) ar-
       chitecture.

       Glibc uses the BSD version if the _BSD_SOURCE feature test macro is de-
       fined   and  none  of  _POSIX_SOURCE,  _POSIX_C_SOURCE,  _XOPEN_SOURCE,
       _GNU_SOURCE, or _SVID_SOURCE is defined.  Otherwise, the System V  ver-
       sion is used, and feature test macros must be defined as follows to ob-
       tain the declaration:

       *  Since glibc 2.26: _XOPEN_SOURCE >= 500

       *  Glibc 2.25 and earlier: _XOPEN_SOURCE

       Since glibc 2.19, only the System V version is exposed  by  <signal.h>;
       applications that formerly used the BSD sigpause() should be amended to
       use sigsuspend(2).

SEE ALSO
       kill(2),  sigaction(2),  sigprocmask(2),  sigsuspend(2),   sigblock(3),
       sigvec(3), feature_test_macros(7)

COLOPHON
       This  page  is  part of release 5.05 of the Linux man-pages project.  A
       description of the project, information about reporting bugs,  and  the
       latest     version     of     this    page,    can    be    found    at
       https://www.kernel.org/doc/man-pages/.

Linux                             2017-09-15                       SIGPAUSE(3)