man3/psignal.3

   1 .\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk)
   2 .\"
   3 .\" SPDX-License-Identifier: Linux-man-pages-copyleft
   4 .\"
   5 .\" References consulted:
   6 .\"     Linux libc source code
   7 .\"     Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
   8 .\"     386BSD man pages
   9 .\" Modified Sat Jul 24 18:45:17 1993 by Rik Faith (faith@cs.unc.edu)
  10 .TH PSIGNAL 3  2021-03-22 "GNU" "Linux Programmer's Manual"
  11 .SH NAME
  12 psignal, psiginfo \- print signal description
  13 .SH LIBRARY
  14 Standard C library
  15 .RI ( libc ", " \-lc )
  16 .SH SYNOPSIS
  17 .nf
  18 .B #include <signal.h>
  19 .PP
  20 .BI "void psignal(int " sig ", const char *" s );
  21 .BI "void psiginfo(const siginfo_t *" pinfo ", const char *" s );
  22 .fi
  23 .PP
  24 .RS -4
  25 Feature Test Macro Requirements for glibc (see
  26 .BR feature_test_macros (7)):
  27 .RE
  28 .PP
  29 .BR psignal ():
  30 .nf
  31     Since glibc 2.19:
  32             _DEFAULT_SOURCE
  33     Glibc 2.19 and earlier:
  34         _BSD_SOURCE || _SVID_SOURCE
  35 .fi
  36 .PP
  37 .BR psiginfo ():
  38 .nf
  39     _POSIX_C_SOURCE >= 200809L
  40 .fi
  41 .SH DESCRIPTION
  42 The
  43 .BR psignal ()
  44 function displays a message on \fIstderr\fP
  45 consisting of the string \fIs\fP, a colon, a space, a string
  46 describing the signal number \fIsig\fP, and a trailing newline.
  47 If the string \fIs\fP is NULL or empty, the colon and space are omitted.
  48 If \fIsig\fP is invalid,
  49 the message displayed will indicate an unknown signal.
  50 .PP
  51 The
  52 .BR psiginfo ()
  53 function is like
  54 .BR psignal (),
  55 except that it displays information about the signal described by
  56 .IR pinfo ,
  57 which should point to a valid
  58 .I siginfo_t
  59 structure.
  60 As well as the signal description,
  61 .BR psiginfo ()
  62 displays information about the origin of the signal,
  63 and other information relevant to the signal
  64 (e.g., the relevant memory address for hardware-generated signals,
  65 the child process ID for
  66 .BR SIGCHLD ,
  67 and the user ID and process ID of the sender, for signals set using
  68 .BR kill (2)
  69 or
  70 .BR sigqueue (3)).
  71 .SH RETURN VALUE
  72 The
  73 .BR psignal ()
  74 and
  75 .BR psiginfo ()
  76 functions return no value.
  77 .SH VERSIONS
  78 The
  79 .BR psiginfo ()
  80 function was added to glibc in version 2.10.
  81 .SH ATTRIBUTES
  82 For an explanation of the terms used in this section, see
  83 .BR attributes (7).
  84 .ad l
  85 .nh
  86 .TS
  87 allbox;
  88 lbx lb lb
  89 l l l.
  90 Interface       Attribute       Value
  91 T{
  92 .BR psignal (),
  93 .BR psiginfo ()
  94 T}      Thread safety   MT-Safe locale
  95 .TE
  96 .hy
  97 .ad
  98 .sp 1
  99 .SH STANDARDS
 100 POSIX.1-2008, 4.3BSD.
 101 .SH BUGS
 102 In glibc versions up to 2.12,
 103 .BR psiginfo ()
 104 had the following bugs:
 105 .IP * 3
 106 In some circumstances, a trailing newline is not printed.
 107 .\" FIXME . http://sourceware.org/bugzilla/show_bug.cgi?id=12107
 108 .\" Reportedly now fixed; check glibc 2.13
 109 .IP *
 110 Additional details are not displayed for real-time signals.
 111 .\" FIXME . http://sourceware.org/bugzilla/show_bug.cgi?id=12108
 112 .\" Reportedly now fixed; check glibc 2.13
 113 .SH SEE ALSO
 114 .BR sigaction (2),
 115 .BR perror (3),
 116 .BR strsignal (3),
 117 .BR signal (7)