PROLOG

       This  manual  page  is part of the POSIX Programmer's Manual.  The Linux implementation of
       this interface may differ (consult the corresponding Linux  manual  page  for  details  of
       Linux behavior), or the interface may not be implemented on Linux.

NAME

       psiginfo, psignal — print signal information to standard error

SYNOPSIS

       #include <signal.h>

       void psiginfo(const siginfo_t *pinfo, const char *message);
       void psignal(int signum, const char *message);

DESCRIPTION

       The psiginfo() and psignal() functions shall print a message out on stderr associated with
       a signal number. If message is not null and is not  the  empty  string,  then  the  string
       pointed  to  by  the  message  argument  shall  be printed first, followed by a <colon>, a
       <space>, and the  signal  description  string  indicated  by  signum,  or  by  the  signal
       associated with pinfo.  If the message argument is null or points to an empty string, then
       only the  signal  description  shall  be  printed.  For  psiginfo(),  the  argument  pinfo
       references  a  valid  siginfo_t  structure. For psignal(), if signum is not a valid signal
       number, the behavior is implementation-defined.

       The psiginfo() and psignal() functions shall not change the orientation  of  the  standard
       error stream.

       The  psiginfo()  and  psignal() functions shall mark for update the last data modification
       and last file status change timestamps of the file  associated  with  the  standard  error
       stream  at  some  time  between  their  successful  completion and exit(), abort(), or the
       completion of fflush() or fclose() on stderr.

       The psiginfo()  and  psignal()  functions  shall  not  change  the  setting  of  errno  if
       successful.

       On  error,  the  psiginfo()  and psignal() functions shall set the error indicator for the
       stream to which stderr points, and shall set errno to indicate the error.

       Since no value is returned, an application wishing to check for  error  situations  should
       set errno to 0, then call psiginfo() or psignal(), then check errno.

RETURN VALUE

       These functions shall not return a value.

ERRORS

       Refer to fputc().

       The following sections are informative.

EXAMPLES

       None.

APPLICATION USAGE

       As  an alternative to setting errno to zero before the call and checking if it is non-zero
       afterwards, applications can use  ferror()  to  detect  whether  psiginfo()  or  psignal()
       encountered an error.

       An  application  wishing  to  use  this  method  to check for error situations should call
       clearerr(stderr) before calling psiginfo() or psignal(), then  if  ferror(stderr)  returns
       non-zero, the value of errno indicates which error occurred.

RATIONALE

       System  V  historically  has  psignal()  and  psiginfo()  in  <siginfo.h>.   However,  the
       <siginfo.h> header is not specified in the Base Definitions volume  of  POSIX.1‐2008,  and
       the type siginfo_t is defined in <signal.h>.

FUTURE DIRECTIONS

       None.

SEE ALSO

       fputc(), perror(), strsignal()

       The Base Definitions volume of POSIX.1‐2008, <signal.h>

COPYRIGHT

       Portions  of  this  text  are  reprinted  and  reproduced in electronic form from IEEE Std
       1003.1, 2013 Edition, Standard for Information Technology  --  Portable  Operating  System
       Interface  (POSIX),  The Open Group Base Specifications Issue 7, Copyright (C) 2013 by the
       Institute of Electrical and Electronics Engineers, Inc  and  The  Open  Group.   (This  is
       POSIX.1-2008  with  the  2013  Technical  Corrigendum  1  applied.)  In  the  event of any
       discrepancy between this version and the original IEEE and The Open  Group  Standard,  the
       original  IEEE  and The Open Group Standard is the referee document. The original Standard
       can be obtained online at http://www.unix.org/online.html .

       Any typographical or formatting errors that appear in this page are most  likely  to  have
       been  introduced  during  the conversion of the source files to man page format. To report
       such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .