1 /* Close standard output and standard error, exiting with a diagnostic on error.
   2 
   3    Copyright (C) 1998, 1999, 2000, 2001, 2002, 2004, 2006 Free
   4    Software Foundation, Inc.
   5 
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2, or (at your option)
   9    any later version.
  10 
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15 
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software Foundation,
  18    Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
  19 
  20 #include <config.h>
  21 
  22 #include "closeout.h"
  23 
  24 #include <errno.h>
  25 #include <stdio.h>
  26 #include <unistd.h>
  27 
  28 #include "gettext.h"
  29 #define _(msgid) gettext (msgid)
  30 
  31 #include "close-stream.h"
  32 #include "error.h"
  33 #include "exitfail.h"
  34 #include "quotearg.h"
  35 
  36 static const char *file_name;
  37 
  38 /* Set the file name to be reported in the event an error is detected
  39    by close_stdout.  */
  40 void
  41 close_stdout_set_file_name (const char *file)
  42 {
  43   file_name = file;
  44 }
  45 
  46 /* Close standard output.  On error, issue a diagnostic and _exit
  47    with status 'exit_failure'.
  48 
  49    Also close standard error.  On error, _exit with status 'exit_failure'.
  50 
  51    Since close_stdout is commonly registered via 'atexit', POSIX
  52    and the C standard both say that it should not call 'exit',
  53    because the behavior is undefined if 'exit' is called more than
  54    once.  So it calls '_exit' instead of 'exit'.  If close_stdout
  55    is registered via atexit before other functions are registered,
  56    the other functions can act before this _exit is invoked.
  57 
  58    Applications that use close_stdout should flush any streams
  59    other than stdout and stderr before exiting, since the call to
  60    _exit will bypass other buffer flushing.  Applications should
  61    be flushing and closing other streams anyway, to check for I/O
  62    errors.  Also, applications should not use tmpfile, since _exit
  63    can bypass the removal of these files.
  64 
  65    It's important to detect such failures and exit nonzero because many
  66    tools (most notably `make' and other build-management systems) depend
  67    on being able to detect failure in other tools via their exit status.  */
  68 
  69 void
  70 close_stdout (void)
  71 {
  72   if (close_stream (stdout) != 0)
  73     {
  74       char const *write_error = _("write error");
  75       if (file_name)
  76         error (0, errno, "%s: %s", quotearg_colon (file_name),
  77                write_error);
  78       else
  79         error (0, errno, "%s", write_error);
  80 
  81       _exit (exit_failure);
  82     }
  83 
  84    if (close_stream (stderr) != 0)
  85      _exit (exit_failure);
  86 }