redhat man page for tempnam

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

NAME
       tempnam - create a name for a temporary file

SYNOPSIS
       #include <stdio.h>

       char *tempnam(const char *dir, const char *pfx);

DESCRIPTION
       The tempnam() function returns a pointer to a string that is a valid filename, and such that a file with this name did not exist when temp-
       nam() checked.  The filename suffix of the pathname generated will start with pfx in case pfx is a non-NULL string of at most  five  bytes.
       The  directory  prefix  part of the pathname generated is required to be `appropriate' (often that at least implies writable).  Attempts to
       find an appropriate directory go through the following steps: (i) In case the environment variable TMPDIR exists and contains the  name	of
       an  appropriate	directory,  that  is used.  (ii) Otherwise, if the dir argument is non-NULL and appropriate, it is used.  (iii) Otherwise,
       P_tmpdir (as defined in <stdio.h>) is used when appropriate.  (iv) Finally an implementation-defined directory may be used.

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

ERRORS
       ENOMEM Allocation of storage failed.

NOTES
       SUSv2 does not mention the use of TMPDIR; glibc will use it only when the program is not suid.  SVID2 specifies	that  the  directory  used
       under (iv) is /tmp.  SVID2 specifies that the string returned by tempnam() was allocated using malloc(3) and hence can be freed by free(3).

       The  tempnam()  function  generates  a different string each time it is called, up to TMP_MAX (defined in <stdio.h>) times. If it is called
       more than TMP_MAX times, the behaviour is implementation defined.

       In case the pfx argument has length larger than five, glibc will use the first five bytes.  Upon failure to find a unique name, glibc  will
       return EEXIST.

BUGS
       The  precise meaning of `appropriate' is undefined; it is unspecified how accessibility of a directory is determined.  Never use this func-
       tion. Use mkstemp(3) instead.

CONFORMING TO
       SVID 2, BSD 4.3

SEE ALSO
       mktemp(3), mkstemp(3), tmpfile(3), tmpnam(3)

								    1999-06-14								TEMPNAM(3)