shm_has_var Check whether a specific entry exists &reftitle.description; boolshm_has_var resourceshm_identifier intvariable_key Checks whether a specific key exists inside a shared memory segment. &reftitle.parameters; shm_identifier Shared memory segment, obtained from shm_attach. variable_key The variable key. &reftitle.returnvalues; Returns &true; if the entry exists, otherwise &false; &reftitle.seealso; shm_get_var shm_put_var