gcc/libiberty/tmpnam.c
Joseph Myers 7f8fa05dae alloca.c, [...]: Improve manual formatting.
* alloca.c, clock.c, getcwd.c, getpagesize.c, getpwd.c, index.c,
	libiberty.texi, memchr.c, putenv.c, rindex.c, strchr.c, strdup.c,
	strerror.c, strrchr.c, strstr.c, strtod.c, tmpnam.c, vfork.c,
	xatexit.c, xmalloc.c, xstrerror.c: Improve manual formatting.  Fix
	spelling.  Give names to function arguments in documentation.  Use
	(void) prototypes in documentation.
	* functions.texi: Regenerate.

From-SVN: r46068
2001-10-07 22:53:31 +01:00

54 lines
1.0 KiB
C

/*
@deftypefn Supplemental char* tmpnam (char *@var{s})
This function attempts to create a name for a temporary file, which
will be a valid file name yet not exist when @code{tmpnam} checks for
it. @var{s} must point to a buffer of at least @code{L_tmpnam} bytes,
or be @code{NULL}. Use of this function creates a security risk, and it must
not be used in new projects. Use @code{mkstemp} instead.
@end deftypefn
*/
#include <stdio.h>
#ifndef L_tmpnam
#define L_tmpnam 100
#endif
#ifndef P_tmpdir
#define P_tmpdir "/usr/tmp"
#endif
static char tmpnam_buffer[L_tmpnam];
static int tmpnam_counter;
extern int getpid ();
char *
tmpnam (s)
char *s;
{
int pid = getpid ();
if (s == NULL)
s = tmpnam_buffer;
/* Generate the filename and make sure that there isn't one called
it already. */
while (1)
{
FILE *f;
sprintf (s, "%s/%s%x.%x", P_tmpdir, "t", pid, tmpnam_counter);
f = fopen (s, "r");
if (f == NULL)
break;
tmpnam_counter++;
fclose (f);
}
return s;
}