How can the "open_basedir restriction" error be resolved when trying to include a file in PHP?

The "open_basedir restriction" error occurs when PHP is unable to access a file due to restrictions set by the open_basedir directive in the php.ini file. To resolve this error, you can either adjust the open_basedir directive in the php.ini file to include the directory where the file is located, or you can move the file to a directory that is allowed by the open_basedir directive.

ini_set('open_basedir', '/path/to/allowed/directory');
include '/path/to/file.php';