stdio-common/tempnam.c

   1 /* Copyright (C) 1991,1993,1996-2000,2007,2009 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, write to the Free
  16    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  17    02111-1307 USA.  */
  18
  19 #include <stdio.h>
  20 #include <string.h>
  21
  22 /* Generate a unique temporary filename using up to five characters of
  23    PFX if it is not NULL.  The directory to put this file in is
  24    searched for as follows: First the environment variable "TMPDIR" is
  25    checked.  If it contains the name of a directory, that directory is
  26    used.  If not and if DIR is not NULL, that value is checked.  If
  27    that fails, P_tmpdir is tried and finally "/tmp".  The storage for
  28    the filename is allocated by `malloc'.  */
  29 char *
  30 tempnam (const char *dir, const char *pfx)
  31 {
  32   char buf[FILENAME_MAX];
  33
  34   if (__path_search (buf, FILENAME_MAX, dir, pfx, 1))
  35     return NULL;
  36
  37   if (__gen_tempname (buf, 0, 0, __GT_NOCREATE))
  38     return NULL;
  39
  40   return __strdup (buf);
  41 }
  42
  43 link_warning (tempnam,
  44               "the use of `tempnam' is dangerous, better use `mkstemp'")