summaryrefslogtreecommitdiff
path: root/lib/closeout.c
blob: f828d0defe5c6d7896f125d483d344bee90b4573 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
/* closeout.c - close standard output
   Copyright (C) 1998, 1999 Free Software Foundation, Inc.

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

   This program 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 General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software Foundation,
   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

#if HAVE_CONFIG_H
# include <config.h>
#endif

#if ENABLE_NLS
# include <libintl.h>
# define _(Text) gettext (Text)
#else
# define _(Text) Text
#endif

#if HAVE_STDLIB_H
# include <stdlib.h>
#endif
#ifndef EXIT_FAILURE
# define EXIT_FAILURE 1
#endif

#include <errno.h>
#ifndef errno
extern int errno;
#endif

#include <stdio.h>
#include "closeout.h"
#include "error.h"

/* Close standard output, exiting with status STATUS on failure.
   If a program writes *anything* to stdout, that program should close
   stdout and make sure that the close succeeds.  Otherwise, suppose that
   you go to the extreme of checking the return status of every function
   that does an explicit write to stdout.  The last printf can succeed in
   writing to the internal stream buffer, and yet the fclose(stdout) could
   still fail (due e.g., to a disk full error) when it tries to write
   out that buffered data.  Thus, you would be left with an incomplete
   output file and the offending program would exit successfully.

   Besides, it's wasteful to check the return value from every call
   that writes to stdout -- just let the internal stream state record
   the failure.  That's what the ferror test is checking below.

   It's important to detect such failures and exit nonzero because many
   tools (most notably `make' and other build-management systems) depend
   on being able to detect failure in other tools via their exit status.  */
void
close_stdout_status (int status)
{
  if (ferror (stdout))
    error (status, 0, _("write error"));
  if (fclose (stdout) != 0)
    error (status, errno, _("write error"));
}

/* Close standard output, exiting with status EXIT_FAILURE on failure.  */
void
close_stdout (void)
{
  close_stdout_status (EXIT_FAILURE);
}