1.\" Copyright (c) 1983, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 4. Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.\" @(#)psignal.3 8.2 (Berkeley) 2/27/95 29.\" $FreeBSD$ 30.\" 31.Dd May 30, 2016 32.Dt PSIGNAL 3 33.Os 34.Sh NAME 35.Nm psignal , 36.Nm strsignal , 37.Nm sys_siglist , 38.Nm sys_signame 39.Nd system signal messages 40.Sh LIBRARY 41.Lb libc 42.Sh SYNOPSIS 43.In signal.h 44.Ft void 45.Fn psignal "int sig" "const char *s" 46.Vt extern const char * const sys_siglist[] ; 47.Vt extern const char * const sys_signame[] ; 48.In string.h 49.Ft "char *" 50.Fn strsignal "int sig" 51.Sh DESCRIPTION 52The 53.Fn psignal 54and 55.Fn strsignal 56functions locate the descriptive message 57string for a signal number. 58.Pp 59The 60.Fn strsignal 61function accepts a signal number argument 62.Fa sig 63and returns a pointer to the corresponding message string. 64.Pp 65The 66.Fn psignal 67function accepts a signal number argument 68.Fa sig 69and writes it to the standard error. 70If the argument 71.Fa s 72is 73.Pf non- Dv NULL 74and does not point to the null character, 75.Fa s 76is written to the standard error file descriptor 77prior to the message string, 78immediately followed by a colon and a space. 79If the signal number is not recognized 80.Pq Xr sigaction 2 , 81the string 82.Dq "Unknown signal" 83is produced. 84.Pp 85The message strings can be accessed directly 86through the external array 87.Va sys_siglist , 88indexed by recognized signal numbers. 89The external array 90.Va sys_signame 91is used similarly and 92contains short, upper-case abbreviations for signals 93which are useful for recognizing signal names 94in user input. 95The defined variable 96.Dv NSIG 97contains a count of the strings in 98.Va sys_siglist 99and 100.Va sys_signame . 101.Sh SEE ALSO 102.Xr sigaction 2 , 103.Xr perror 3 , 104.Xr strerror 3 105.Sh HISTORY 106The 107.Fn psignal 108function appeared in 109.Bx 4.2 . 110