glibc/stdio-common/tmpnam.c
1996-10-02 01:40:17 +00:00

50 lines
1.6 KiB
C

/* Copyright (C) 1991, 1993, 1996 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., 675 Mass Ave,
Cambridge, MA 02139, USA. */
#include <stdio.h>
#include <string.h>
/* Generate a unique filename in P_tmpdir.
This function is *not* thread safe! */
char *
tmpnam (char *s)
{
/* By using two buffers we manage to be thread safe in the case
where S != NULL. */
static char buf[L_tmpnam];
char tmpbuf[L_tmpnam];
char *result;
/* 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 FILENAME_MAX characters in any case. */
result = __stdio_gen_tempname (s ?: tmpbuf, L_tmpnam, (const char *) NULL,
(const char *) NULL, 0,
(size_t *) NULL, (FILE **) NULL);
if (result != NULL && s == NULL)
{
memcpy (buf, result, L_tmpnam);
result = buf;
}
return result;
}