Create file with unique file name

Description

tempnam(string $directory, string $prefix): string|false

Creates a file with a unique filename, with access permission set to 0600, in the specified directory. If the directory does not exist or is not writable, tempnam() may generate a file in the system's temporary directory, and return the full path to that file, including its name.

Parameters

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

Note: Only the first 63 characters of the prefix are used, the rest are ignored. Windows uses only the first three characters of the prefix.

Return Values

Returns the new temporary filename (with path), or false on failure.

Changelog

Version	Description
7.1.0	tempnam() now emits a notice when falling back to the temp directory of the system.

Examples

Example #1 tempnam() example


<?php
$tmpfname = tempnam("/tmp", "FOO");

$handle = fopen($tmpfname, "w");
fwrite($handle, "writing to tempfile");
fclose($handle);

// do something here

unlink($tmpfname);
?>

Notes

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

tempnam