| /* Compare two open file descriptors to see if they refer to the same file. |
| Copyright (C) 1991-2020 Free Software Foundation, Inc. |
| |
| This file is part of the libiberty library. |
| Libiberty 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. |
| |
| Libiberty 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 libiberty; see the file COPYING.LIB. If |
| not, write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor, |
| Boston, MA 02110-1301, USA. */ |
| |
| |
| /* |
| |
| @deftypefn Extension int fdmatch (int @var{fd1}, int @var{fd2}) |
| |
| Check to see if two open file descriptors refer to the same file. |
| This is useful, for example, when we have an open file descriptor for |
| an unnamed file, and the name of a file that we believe to correspond |
| to that fd. This can happen when we are exec'd with an already open |
| file (@code{stdout} for example) or from the SVR4 @file{/proc} calls |
| that return open file descriptors for mapped address spaces. All we |
| have to do is open the file by name and check the two file descriptors |
| for a match, which is done by comparing major and minor device numbers |
| and inode numbers. |
| |
| @end deftypefn |
| |
| BUGS |
| |
| (FIXME: does this work for networks?) |
| It works for NFS, which assigns a device number to each mount. |
| |
| */ |
| |
| #ifdef HAVE_CONFIG_H |
| #include "config.h" |
| #endif |
| #include "ansidecl.h" |
| #include "libiberty.h" |
| #include <sys/types.h> |
| #include <sys/stat.h> |
| |
| int fdmatch (int fd1, int fd2) |
| { |
| struct stat sbuf1; |
| struct stat sbuf2; |
| |
| if ((fstat (fd1, &sbuf1) == 0) && |
| (fstat (fd2, &sbuf2) == 0) && |
| (sbuf1.st_dev == sbuf2.st_dev) && |
| (sbuf1.st_ino == sbuf2.st_ino)) |
| { |
| return (1); |
| } |
| else |
| { |
| return (0); |
| } |
| } |