Creates a file with a unique filename, with access permission set to 0600, 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
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
dirparameter, it falls back on the system default.
Returns the new temporary filename, or FALSE on failure.
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.