sigpause - atomically release blocked signals and wait for interrupt


   #include <signal.h>

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

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


   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.


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


   For   an   explanation   of   the  terms  used  in  this  section,  see

   Interface   Attribute      Value   
   sigpause()  Thread safety  MT-Safe 


   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.


   The classical BSD version of this function appeared in 4.2BSD.  It sets
   the process's  signal  mask  to  sigmask.   UNIX  95  standardized  the
   incompatible  System V version of this function, which removes only the
   specified signal sig from the process's signal mask.   The  unfortunate
   situation 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)

   Glibc uses the BSD version if the _BSD_SOURCE  feature  test  macro  is
   defined  and  none  of  _POSIX_SOURCE,  _POSIX_C_SOURCE, _XOPEN_SOURCE,
   _GNU_SOURCE, or _SVID_SOURCE  is  defined.   Otherwise,  the  System  V
   version  is  used  (and  _XOPEN_SOURCE  must  be  defined to obtain the
   declaration).  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).


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


   This  page  is  part of release 4.09 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


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