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TMPNAM(3) Linux Programmer's Manual TMPNAM(3)

NAME

tmpnam - create a name for a temporary file

SYNOPSIS

#include <stdio.h>

char *tmpnam(char *s);

DESCRIPTION

The tmpnam() function returns a pointer to a string that is a valid filename, and such that a file with this name did not exist at some point in time, so that naive programmers may think it a suitable name for a temporary file. If the argument s is NULL this name is generated in an internal static buffer and may be overwritten by the next call to tmpnam(). If s is not NULL, the name is copied to the character array (of length at least L_tmpnam) pointed at by s and the value s is returned in case of success.

The path name that is created, has a directory prefix P_tmpdir. (Both L_tmpnam and P_tmpdir are defined in <stdio.h>, just like the TMP_MAX mentioned below.)

RETURN VALUE

The tmpnam() function returns a pointer to a unique temporary filename, or NULL if a unique name cannot be generated.

ERRORS

No errors are defined.

NOTES

Portable applications that use threads cannot call tmpnam() with NULL parameter if either _POSIX_THREAD_SAFE_FUNCTIONS or _POSIX_THREADS is defined.

The tmpnam() function generates a different string each time it is called, up to TMP_MAX times. If it is called more than TMP_MAX times, the behaviour is implementation defined.

BUGS

Never use this function. Use mkstemp(3) instead.

CONFORMING TO

SVID 2, POSIX, BSD 4.3, ISO 9899

SEE ALSO

mktemp(3), mkstemp(3), tempnam(3), tmpfile(3)

14 June 1999