1298:/std/door.c (/std/door.c)
(void) set_knock_command(mixed cmd)
/*
 * Function name:	set_knock_command
 * Description	:	set the list of commands for knocking on the door
 * Arguments	:	mixed cmd -- a command string or an array of 
 *			command strings, or 0 to disable 'knock'.
 *			The default command is ({ "knock", "pound" }).
 */
