putenv()
putenv() — Sets the value of an environment variable.
Built-in function of PHP 8.5. The manual lists it as available in PHP 4, PHP 5, PHP 7, PHP 8. This page is the reference card: signature, parameters and return value, plus the changelog and the example the manual provides.
What it does
Adds assignment to the server environment. The environment variable will only exist for the duration of the current request. At the end of the request the environment is restored to its original state.
Signature
putenv(string $assignment): bool
Parameters
| Parameter | Type | What it takes |
|---|---|---|
| $assignment | string | The setting, like "FOO=BAR" |
Return value
Returns true on success or false on failure.
Example
A runnable snippet:
putenv("UNIQID=$uniqid");
See also
All PHP 8.5 built-in functions
Reference card built from the PHP manual page putenv() (PHP documentation, CC BY 3.0). The page is generated from the manual, so the wording of the parameter and return value text follows php.net.