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glibc  2.9
tmpfile.c
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00001 /* Open a stdio stream on an anonymous temporary file.  Generic/POSIX version.
00002    Copyright (C) 1991,1993,1996-2000,2002,2003,2007
00003    Free Software Foundation, Inc.
00004    This file is part of the GNU C Library.
00005 
00006    The GNU C Library is free software; you can redistribute it and/or
00007    modify it under the terms of the GNU Lesser General Public
00008    License as published by the Free Software Foundation; either
00009    version 2.1 of the License, or (at your option) any later version.
00010 
00011    The GNU C Library is distributed in the hope that it will be useful,
00012    but WITHOUT ANY WARRANTY; without even the implied warranty of
00013    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00014    Lesser General Public License for more details.
00015 
00016    You should have received a copy of the GNU Lesser General Public
00017    License along with the GNU C Library; if not, write to the Free
00018    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
00019    02111-1307 USA.  */
00020 
00021 #include <fcntl.h>
00022 #include <stdio.h>
00023 #include <unistd.h>
00024 
00025 #ifdef USE_IN_LIBIO
00026 # include <iolibio.h>
00027 # define __fdopen INTUSE(_IO_fdopen)
00028 # ifndef tmpfile
00029 #  define tmpfile __new_tmpfile
00030 # endif
00031 #endif
00032 
00033 
00034 /* This returns a new stream opened on a temporary file (generated
00035    by tmpnam).  The file is opened with mode "w+b" (binary read/write).
00036    If we couldn't generate a unique filename or the file couldn't
00037    be opened, NULL is returned.  */
00038 FILE *
00039 tmpfile (void)
00040 {
00041   char buf[FILENAME_MAX];
00042   int fd;
00043   FILE *f;
00044 
00045   if (__path_search (buf, FILENAME_MAX, NULL, "tmpf", 0))
00046     return NULL;
00047   int flags = 0;
00048 #ifdef FLAGS
00049   flags = FLAGS;
00050 #endif
00051   fd = __gen_tempname (buf, flags, __GT_FILE);
00052   if (fd < 0)
00053     return NULL;
00054 
00055   /* Note that this relies on the Unix semantics that
00056      a file is not really removed until it is closed.  */
00057   (void) __unlink (buf);
00058 
00059   if ((f = __fdopen (fd, "w+b")) == NULL)
00060     __close (fd);
00061 
00062   return f;
00063 }
00064 
00065 #if defined USE_IN_LIBIO && !defined FLAGS /* Not for tmpfile64.  */
00066 # undef tmpfile
00067 # include <shlib-compat.h>
00068 versioned_symbol (libc, __new_tmpfile, tmpfile, GLIBC_2_1);
00069 #endif