PHP Manual: Create file with unique file name

Description

string tempnam ( string $dir , string $prefix )

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.

Parameters

dir: The directory where the temporary filename will be created.
prefix: The prefix of the generated temporary filename.

Note: Windows uses only the first three characters of prefix.

Return Values

Returns the new temporary filename, or FALSE on failure.

Changelog

Version	Description
4.0.6	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.
4.0.3	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.

Examples

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);
?>

Notes

Note: If PHP cannot create a file in the specified dir parameter, it falls back on the system default. On NTFS this also happens if the specified dir contains more than 65534 files.

tempnam