# zx_object_signal ## NAME object_signal - signal an object ## SYNOPSIS ``` #include zx_status_t zx_object_signal(zx_handle_t handle, uint32_t clear_mask, uint32_t set_mask); ``` ## DESCRIPTION `zx_object_signal()` asserts and deasserts the userspace-accessible signal bits on an object. Most of the 32 signals are reserved for system use and are assigned to per-object functions, like **ZX_CHANNEL_READABLE** or **ZX_TASK_TERMINATED**. There are 8 signal bits available for userspace processes to use as they see fit: **ZX_USER_SIGNAL_0** through **ZX_USER_SIGNAL_7**. *Event* objects also allow control over the **ZX_EVENT_SIGNALED** bit. *Eventpair* objects also allow control over the **ZX_EVENTPAIR_SIGNALED** bit. The *clear_mask* is first used to clear any bits indicated, and then the *set_mask* is used to set any bits indicated. ## RIGHTS *handle* must be of type **ZX_OBJ_TYPE_PROCESS** and have **ZX_RIGHT_SIGNAL**. ## RETURN VALUE `zx_object_signal()` returns **ZX_OK** on success. In the event of failure, a negative error value is returned. ## ERRORS **ZX_ERR_BAD_HANDLE** *handle* is not a valid handle. **ZX_ERR_ACCESS_DENIED** *handle* lacks the right **ZX_RIGHT_SIGNAL**. **ZX_ERR_INVALID_ARGS** *clear_mask* or *set_mask* contain bits that are not allowed. ## SEE ALSO - [`zx_event_create()`] - [`zx_eventpair_create()`] - [`zx_object_signal_peer()`] [`zx_event_create()`]: event_create.md [`zx_eventpair_create()`]: eventpair_create.md [`zx_object_signal_peer()`]: object_signal_peer.md