| .\" Copyright (c) 1994 Mike Battersby |
| .\" |
| .\" %%%LICENSE_START(VERBATIM) |
| .\" Permission is granted to make and distribute verbatim copies of this |
| .\" manual provided the copyright notice and this permission notice are |
| .\" preserved on all copies. |
| .\" |
| .\" Permission is granted to copy and distribute modified versions of this |
| .\" manual under the conditions for verbatim copying, provided that the |
| .\" entire resulting derived work is distributed under the terms of a |
| .\" permission notice identical to this one. |
| .\" |
| .\" Since the Linux kernel and libraries are constantly changing, this |
| .\" manual page may be incorrect or out-of-date. The author(s) assume no |
| .\" responsibility for errors or omissions, or for damages resulting from |
| .\" the use of the information contained herein. The author(s) may not |
| .\" have taken the same level of care in the production of this manual, |
| .\" which is licensed free of charge, as they might when working |
| .\" professionally. |
| .\" |
| .\" Formatted or processed versions of this manual, if unaccompanied by |
| .\" the source, must acknowledge the copyright and authors of this work. |
| .\" %%%LICENSE_END |
| .\" |
| .\" Modified by aeb, 960721 |
| .\" 2005-11-21, mtk, added descriptions of sigisemptyset(), sigandset(), |
| .\" and sigorset() |
| .\" 2007-10-26 mdw added wording that a sigset_t must be initialized |
| .\" prior to use |
| .\" |
| .TH SIGSETOPS 3 2016-03-15 "Linux" "Linux Programmer's Manual" |
| .SH NAME |
| sigemptyset, sigfillset, sigaddset, sigdelset, sigismember \- POSIX |
| signal set operations |
| .SH SYNOPSIS |
| .B #include <signal.h> |
| .PP |
| .BI "int sigemptyset(sigset_t *" set ); |
| .PP |
| .BI "int sigfillset(sigset_t *" set ); |
| .PP |
| .BI "int sigaddset(sigset_t *" set ", int " signum ); |
| .PP |
| .BI "int sigdelset(sigset_t *" set ", int " signum ); |
| .PP |
| .BI "int sigismember(const sigset_t *" set ", int " signum ); |
| .PP |
| .in -4n |
| Feature Test Macro Requirements for glibc (see |
| .BR feature_test_macros (7)): |
| .in |
| .PP |
| .ad l |
| .BR sigemptyset (), |
| .BR sigfillset (), |
| .BR sigaddset (), |
| .BR sigdelset (), |
| .BR sigismember (): |
| .RS 4 |
| _POSIX_C_SOURCE |
| .RE |
| .ad b |
| .SH DESCRIPTION |
| These functions allow the manipulation of POSIX signal sets. |
| .PP |
| .BR sigemptyset () |
| initializes the signal set given by |
| .I set |
| to empty, with all signals excluded from the set. |
| .PP |
| .BR sigfillset () |
| initializes |
| .I set |
| to full, including all signals. |
| .PP |
| .BR sigaddset () |
| and |
| .BR sigdelset () |
| add and delete respectively signal |
| .I signum |
| from |
| .IR set . |
| .PP |
| .BR sigismember () |
| tests whether |
| .I signum |
| is a member of |
| .IR set . |
| .PP |
| Objects of type |
| .I sigset_t |
| must be initialized by a call to either |
| .BR sigemptyset () |
| or |
| .BR sigfillset () |
| before being passed to the functions |
| .BR sigaddset (), |
| .BR sigdelset () |
| and |
| .BR sigismember () |
| or the additional glibc functions described below |
| .RB ( sigisemptyset (), |
| .BR sigandset (), |
| and |
| .BR sigorset ()). |
| The results are undefined if this is not done. |
| .SH RETURN VALUE |
| .BR sigemptyset (), |
| .BR sigfillset (), |
| .BR sigaddset (), |
| and |
| .BR sigdelset () |
| return 0 on success and \-1 on error. |
| .PP |
| .BR sigismember () |
| returns 1 if |
| .I signum |
| is a member of |
| .IR set , |
| 0 if |
| .I signum |
| is not a member, and \-1 on error. |
| .PP |
| On error, these functions set |
| .I errno |
| to indicate the cause of the error. |
| .SH ERRORS |
| .TP |
| .B EINVAL |
| .I signum |
| is not a valid signal. |
| .SH ATTRIBUTES |
| For an explanation of the terms used in this section, see |
| .BR attributes (7). |
| .TS |
| allbox; |
| lbw31 lb lb |
| l l l. |
| Interface Attribute Value |
| T{ |
| .BR sigemptyset (), |
| .BR sigfillset (), |
| .br |
| .BR sigaddset (), |
| .BR sigdelset (), |
| .br |
| .BR sigismember (), |
| .BR sigisemptyset (), |
| .br |
| .BR sigorset (), |
| .BR sigandset () |
| T} Thread safety MT-Safe |
| .TE |
| .SH CONFORMING TO |
| POSIX.1-2001, POSIX.1-2008. |
| .SH NOTES |
| When creating a filled signal set, the glibc |
| .BR sigfillset () |
| function does not include the two real-time signals used internally |
| by the NPTL threading implementation. |
| See |
| .BR nptl (7) |
| for details. |
| .\" |
| .SS Glibc extensions |
| If the |
| .B _GNU_SOURCE |
| feature test macro is defined, then \fI<signal.h>\fP |
| exposes three other functions for manipulating signal |
| sets: |
| .PP |
| .nf |
| .BI "int sigisemptyset(const sigset_t *" set ); |
| .BI "int sigorset(sigset_t *" dest ", const sigset_t *" left , |
| .BI " const sigset_t *" right ); |
| .BI "int sigandset(sigset_t *" dest ", const sigset_t *" left , |
| .BI " const sigset_t *" right ); |
| .fi |
| .PP |
| .BR sigisemptyset () |
| returns 1 if |
| .I set |
| contains no signals, and 0 otherwise. |
| .PP |
| .BR sigorset () |
| places the union of the sets |
| .I left |
| and |
| .I right |
| in |
| .IR dest . |
| .BR sigandset () |
| places the intersection of the sets |
| .I left |
| and |
| .I right |
| in |
| .IR dest . |
| Both functions return 0 on success, and \-1 on failure. |
| .PP |
| These functions are nonstandard (a few other systems provide similar |
| functions) and their use should be avoided in portable applications. |
| .SH SEE ALSO |
| .BR sigaction (2), |
| .BR sigpending (2), |
| .BR sigprocmask (2), |
| .BR sigsuspend (2) |