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psignal(3)


NAME

   psignal, psiginfo - print signal message

SYNOPSIS

   #include <signal.h>

   void psignal(int sig, const char *s);
   void psiginfo(const siginfo_t *pinfo, const char *s);

   extern const char *const sys_siglist[];

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

   psignal():
       Since glibc 2.19:
           _DEFAULT_SOURCE
       Glibc 2.19 and earlier:
           _BSD_SOURCE || _SVID_SOURCE
   psiginfo(): _POSIX_C_SOURCE >= 200809L
   sys_siglist:
       Since glibc 2.19:
           _DEFAULT_SOURCE
       Glibc 2.19 and earlier:
           _BSD_SOURCE

DESCRIPTION

   The  psignal()  function displays a message on stderr consisting of the
   string s, a colon, a space, a string describing the signal number  sig,
   and  a  trailing  newline.  If the string s is NULL or empty, the colon
   and space are omitted.  If sig is invalid, the message  displayed  will
   indicate an unknown signal.

   The  psiginfo()  function  is  like  psignal(), except that it displays
   information about the signal described by pinfo, which should point  to
   a  valid  siginfo_t  structure.   As  well  as  the signal description,
   psiginfo() displays information about the origin  of  the  signal,  and
   other  information  relevant  to  the signal (e.g., the relevant memory
   address for  hardware-generated  signals,  the  child  process  ID  for
   SIGCHLD,  and the user ID and process ID of the sender, for signals set
   using kill(2) or sigqueue(3)).

   The array sys_siglist holds the signal description strings  indexed  by
   signal number.

RETURN VALUE

   The psignal() and psiginfo() functions return no value.

VERSIONS

   The psiginfo() function was added to glibc in version 2.10.

ATTRIBUTES

   For   an   explanation   of   the  terms  used  in  this  section,  see
   attributes(7).

   ┌──────────────────────┬───────────────┬────────────────┐
   │Interface             │ Attribute     │ Value          │
   ├──────────────────────┼───────────────┼────────────────┤
   │psignal(), psiginfo() │ Thread safety │ MT-Safe locale │
   └──────────────────────┴───────────────┴────────────────┘

CONFORMING TO

   POSIX.1-2008, 4.3BSD.

BUGS

   In glibc versions up to 2.12, psiginfo() had the following bugs:

   *  In some circumstances, a trailing newline is not printed.

   *  Additional details are not displayed for real-time signals.

SEE ALSO

   sigaction(2), perror(3), strsignal(3), signal(7)

COLOPHON

   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
   https://www.kernel.org/doc/man-pages/.



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