glibc/stdio-common/perror.c

/* Copyright (C) 1991, 1992, 1993, 1997, 1998 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public License as
   published by the Free Software Foundation; either version 2 of the
   License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#include <stdio.h>
#include <string.h>
#include <errno.h>

/* Print a line on stderr consisting of the text in S, a colon, a space,
   a message describing the meaning of the contents of `errno' and a newline.
   If S is NULL or "", the colon and space are omitted.  */
void
perror (const char *s)
{
  char buf[1024];
  int errnum = errno;
  const char *colon;

  if (s == NULL || *s == '\0')
    s = colon = "";
  else
    colon = ": ";

  (void) fprintf (stderr, "%s%s%s\n",
		  s, colon, __strerror_r (errnum, buf, sizeof buf));
}