Description
string 
tempnam ( string dir, string prefix )
     Creates a file with a unique filename in the specified directory.
     If the directory does not exist, tempnam() may
     generate a file in the system's temporary directory, and return
     the name of that. 
    
     Prior to PHP 4.0.6, the behaviour of the
     tempnam() function was system dependent. On
     Windows the TMP environment variable will override the
     dir parameter, on Linux the TMPDIR
     environment variable has precedence, while SVR4 will always use
     your dir parameter if the directory it
     points to exists. Consult your system documentation on the
     tempnam(3) function if in doubt.
    
Note: 
      If PHP cannot create a file in the specified dir
      parameter, it falls back on the system default.
     
     Returns the new temporary filename, or FALSE on
     failure.
     
| Example 1. tempnam() example | 
<?php$tmpfname = tempnam("/tmp", "FOO");
 
 $handle = fopen($tmpfname, "w");
 fwrite($handle, "writing to tempfile");
 fclose($handle);
 
 // do here something
 
 unlink($tmpfname);
 ?>
 | 
 | 
    Note: 
      This function's behavior changed in 4.0.3. The temporary file is also
      created to avoid a race condition where the file might appear in the
      filesystem between the time the string was generated and before
      the script gets around to creating the file. Note, that you need
      to remove the file in case you need it no more, it is not done
      automatically.
     
     See also tmpfile() and unlink().