1115:/d/Genesis/newmagic/spell.c (/d/Genesis/newmagic/spell.c)
(public int) concentrate_spell(object caster, object *targets, string arg)
/*
 * Function name: concentrate_spell
 * Description:   Start concentration on the spell
 * Arguments:     1. (object)   The caster
 *                2. (object *) The targets
 *                3. (string)   The arguments passed to the "cast" command
 * Returns:       0 - Concentration begun
 *                1 - Concentration not begun; spell aborted.
 */
