diff options
| -rw-r--r-- | include/asterisk/sched.h | 16 |
1 files changed, 5 insertions, 11 deletions
diff --git a/include/asterisk/sched.h b/include/asterisk/sched.h index 829a1b0f6..d2508bfa8 100644 --- a/include/asterisk/sched.h +++ b/include/asterisk/sched.h @@ -41,17 +41,11 @@ extern "C" { * then whatever callback had been running will complete * and reinsert the task into the scheduler. * - * Note that this is NOT always appropriate. This should - * only be used for tasks whose callback may return non-zero - * to indicate that the task needs to be rescheduled with the - * SAME id as previously. - * - * Some scheduler callbacks instead may reschedule the task themselves, - * thus removing the previous task id from the queue. If the task is rescheduled - * in this manner, then the id for the task will be different than before - * and so it makes no sense to use this macro. Note that if using the scheduler - * in this manner, it is perfectly acceptable for ast_sched_del to fail, and this - * macro should NOT be used. + * Since macro expansion essentially works like pass-by-name + * parameter passing, this macro will still work correctly even + * if the id of the task to delete changes. This holds as long as + * the name of the id which could change is passed to the macro + * and not a copy of the value of the id. */ #define AST_SCHED_DEL(sched, id) \ ({ \ |