Details | Last modification | View Log | RSS feed
| Rev | Author | Line No. | Line |
|---|---|---|---|
| 5191 | serge | 1 | /* Compare two open file descriptors to see if they refer to the same file. |
| 2 | Copyright (C) 1991 Free Software Foundation, Inc. |
||
| 3 | |||
| 4 | This file is part of the libiberty library. |
||
| 5 | Libiberty is free software; you can redistribute it and/or |
||
| 6 | modify it under the terms of the GNU Library General Public |
||
| 7 | License as published by the Free Software Foundation; either |
||
| 8 | version 2 of the License, or (at your option) any later version. |
||
| 9 | |||
| 10 | Libiberty 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 GNU |
||
| 13 | Library General Public License for more details. |
||
| 14 | |||
| 15 | You should have received a copy of the GNU Library General Public |
||
| 16 | License along with libiberty; see the file COPYING.LIB. If |
||
| 17 | not, write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor, |
||
| 18 | Boston, MA 02110-1301, USA. */ |
||
| 19 | |||
| 20 | |||
| 21 | /* |
||
| 22 | |||
| 23 | @deftypefn Extension int fdmatch (int @var{fd1}, int @var{fd2}) |
||
| 24 | |||
| 25 | Check to see if two open file descriptors refer to the same file. |
||
| 26 | This is useful, for example, when we have an open file descriptor for |
||
| 27 | an unnamed file, and the name of a file that we believe to correspond |
||
| 28 | to that fd. This can happen when we are exec'd with an already open |
||
| 29 | file (@code{stdout} for example) or from the SVR4 @file{/proc} calls |
||
| 30 | that return open file descriptors for mapped address spaces. All we |
||
| 31 | have to do is open the file by name and check the two file descriptors |
||
| 32 | for a match, which is done by comparing major and minor device numbers |
||
| 33 | and inode numbers. |
||
| 34 | |||
| 35 | @end deftypefn |
||
| 36 | |||
| 37 | BUGS |
||
| 38 | |||
| 39 | (FIXME: does this work for networks?) |
||
| 40 | It works for NFS, which assigns a device number to each mount. |
||
| 41 | |||
| 42 | */ |
||
| 43 | |||
| 44 | #ifdef HAVE_CONFIG_H |
||
| 45 | #include "config.h" |
||
| 46 | #endif |
||
| 47 | #include "ansidecl.h" |
||
| 48 | #include "libiberty.h" |
||
| 49 | #include |
||
| 50 | #include |
||
| 51 | |||
| 52 | int fdmatch (int fd1, int fd2) |
||
| 53 | { |
||
| 54 | struct stat sbuf1; |
||
| 55 | struct stat sbuf2; |
||
| 56 | |||
| 57 | if ((fstat (fd1, &sbuf1) == 0) && |
||
| 58 | (fstat (fd2, &sbuf2) == 0) && |
||
| 59 | (sbuf1.st_dev == sbuf2.st_dev) && |
||
| 60 | (sbuf1.st_ino == sbuf2.st_ino)) |
||
| 61 | { |
||
| 62 | return (1); |
||
| 63 | } |
||
| 64 | else |
||
| 65 | { |
||
| 66 | return (0); |
||
| 67 | } |
||
| 68 | } |