sigpause(3)

1sigpause(3)                Library Functions Manual                sigpause(3)
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NAME

6       sigpause - atomically release blocked signals and wait for interrupt
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LIBRARY

9       Standard C library (libc, -lc)
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SYNOPSIS

12       #include <signal.h>
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14       [[deprecated]] int sigpause(int sigmask);  /* BSD (but see NOTES) */
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16       [[deprecated]] int sigpause(int sig);      /* POSIX.1 / SysV / UNIX 95 */
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DESCRIPTION

19       Don't use this function.  Use sigsuspend(2) instead.
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21       The  function  sigpause()  is  designed  to  wait  for some signal.  It
22       changes the process's signal mask (set of blocked  signals),  and  then
23       waits  for  a signal to arrive.  Upon arrival of a signal, the original
24       signal mask is restored.
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RETURN VALUE

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

31       For  an  explanation  of  the  terms  used  in  this  section,  see at‐
32       tributes(7).
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34       ┌────────────────────────────────────────────┬───────────────┬─────────┐
35       │Interface                                   │ Attribute     │ Value   │
36       ├────────────────────────────────────────────┼───────────────┼─────────┤
37       │sigpause()                                  │ Thread safety │ MT-Safe │
38       └────────────────────────────────────────────┴───────────────┴─────────┘
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VERSIONS

41       On Linux, this routine is a system call only on the Sparc (sparc64) ar‐
42       chitecture.
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44       glibc uses the BSD version if the _BSD_SOURCE feature test macro is de‐
45       fined  and  none  of  _POSIX_SOURCE,  _POSIX_C_SOURCE,   _XOPEN_SOURCE,
46       _GNU_SOURCE,  or _SVID_SOURCE is defined.  Otherwise, the System V ver‐
47       sion is used, and feature test macros must be defined as follows to ob‐
48       tain the declaration:
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50       •  Since glibc 2.26: _XOPEN_SOURCE >= 500
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52       •  glibc 2.25 and earlier: _XOPEN_SOURCE
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54       Since  glibc  2.19, only the System V version is exposed by <signal.h>;
55       applications that formerly used the BSD sigpause() should be amended to
56       use sigsuspend(2).
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STANDARDS

59       POSIX.1-2008.
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HISTORY

62       POSIX.1-2001.  Obsoleted in POSIX.1-2008.
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64       The classical BSD version of this function appeared in 4.2BSD.  It sets
65       the process's signal mask to sigmask.  UNIX 95 standardized the  incom‐
66       patible System V version of this function, which removes only the spec‐
67       ified signal sig from the process's signal mask.  The unfortunate situ‐
68       ation  with two incompatible functions with the same name was solved by
69       the sigsuspend(2) function, that takes a sigset_t *  argument  (instead
70       of an int).
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