/* Copyright (C) 1991, 1993, 1996, 1997, 1998 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library 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. The GNU C Library 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 the GNU C Library; see the file COPYING.LIB. If not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include <stdio.h> #include <string.h> extern int __path_search (char *tmpl, size_t tmpl_len, const char *dir, const char *pfx, int try_tmpdir); extern int __gen_tempname (char *tmpl, int openit); static char tmpnam_buffer[L_tmpnam]; /* Generate a unique filename in P_tmpdir. This function is *not* thread safe when S == NULL! */ char * tmpnam (char *s) { /* By using two buffers we manage to be thread safe in the case where S != NULL. */ char tmpbuf[L_tmpnam]; /* In the following call we use the buffer pointed to by S if non-NULL although we don't know the size. But we limit the size to L_tmpnam characters in any case. */ if (__path_search (s ? : tmpbuf, L_tmpnam, NULL, NULL, 0)) return NULL; if (__gen_tempname (s ? : tmpbuf, 0)) return NULL; if (s == NULL) return (char *) memcpy (tmpnam_buffer, tmpbuf, L_tmpnam); return s; }