Get the filesystem directory path (with trailing slash) for the plugin __FILE__ passed in.

Signature

plugin_dir_path( $file )
file
 (string) The filename of the plugin (__FILE__).

Return

(string) the filesystem path of the directory that contains the plugin.

Source

function plugin_dir_path( $file ) {
	return trailingslashit( dirname( $file ) );
}
WP Trac GitHub

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