Mercurial > gnulib
annotate lib/fd-safer.c @ 40057:b06060465f09
maint: Run 'make update-copyright'
| author | Paul Eggert <eggert@cs.ucla.edu> |
|---|---|
| date | Tue, 01 Jan 2019 00:25:11 +0100 |
| parents | 10eb9086bea0 |
| children |
| rev | line source |
|---|---|
| 5813 | 1 /* Return a safer copy of a file descriptor. |
| 2 | |
|
40057
b06060465f09
maint: Run 'make update-copyright'
Paul Eggert <eggert@cs.ucla.edu>
parents:
19484
diff
changeset
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3 Copyright (C) 2005-2006, 2009-2019 Free Software Foundation, Inc. |
| 5813 | 4 |
|
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Change copyright notice from GPLv2+ to GPLv3+.
Bruno Haible <bruno@clisp.org>
parents:
7302
diff
changeset
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5 This program is free software: you can redistribute it and/or modify |
| 5813 | 6 it under the terms of the GNU General Public License as published by |
|
9309
bbbbbf4cd1c5
Change copyright notice from GPLv2+ to GPLv3+.
Bruno Haible <bruno@clisp.org>
parents:
7302
diff
changeset
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7 the Free Software Foundation; either version 3 of the License, or |
|
bbbbbf4cd1c5
Change copyright notice from GPLv2+ to GPLv3+.
Bruno Haible <bruno@clisp.org>
parents:
7302
diff
changeset
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8 (at your option) any later version. |
| 5813 | 9 |
| 10 This program is distributed in the hope that it will be useful, | |
| 11 but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
| 13 GNU General Public License for more details. | |
| 14 | |
| 15 You should have received a copy of the GNU General Public License | |
| 19190 | 16 along with this program. If not, see <https://www.gnu.org/licenses/>. */ |
| 5813 | 17 |
| 18 /* Written by Paul Eggert. */ | |
| 19 | |
|
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* _fpending.c: Include <config.h> unconditionally, since we no
Paul Eggert <eggert@cs.ucla.edu>
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20 #include <config.h> |
| 5813 | 21 |
| 22 #include "unistd-safer.h" | |
| 23 | |
| 24 #include <errno.h> | |
|
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Merge minor changes from coreutils.
Jim Meyering <jim@meyering.net>
parents:
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25 #include <unistd.h> |
| 5813 | 26 |
| 27 /* Return FD, unless FD would be a copy of standard input, output, or | |
| 28 error; in that case, return a duplicate of FD, closing FD. On | |
| 29 failure to duplicate, close FD, set errno, and return -1. Preserve | |
| 30 errno if FD is negative, so that the caller can always inspect | |
| 31 errno when the returned value is negative. | |
| 32 | |
| 33 This function is usefully wrapped around functions that return file | |
| 34 descriptors, e.g., fd_safer (open ("file", O_RDONLY)). */ | |
| 35 | |
| 36 int | |
| 37 fd_safer (int fd) | |
| 38 { | |
| 39 if (STDIN_FILENO <= fd && fd <= STDERR_FILENO) | |
| 40 { | |
| 41 int f = dup_safer (fd); | |
| 42 int e = errno; | |
| 43 close (fd); | |
| 44 errno = e; | |
| 45 fd = f; | |
| 46 } | |
| 47 | |
| 48 return fd; | |
| 49 } |