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 tempnam() 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 function. Use mkstemp(3) instead.

CONFORMING TO

       SVID 2, BSD 4.3

SEE ALSO

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

                                                  14 June 1999                                        TEMPNAM(3)