Summary
Signal an object's peer.
Declaration
#include <zircon/syscalls.h>
zx_status_t zx_object_signal_peer(zx_handle_t handle,
uint32_t clear_mask,
uint32_t set_mask);
Description
zx_object_signal_peer() asserts and deasserts the userspace-accessible
signal bits on the object's peer. An object peer is the opposite endpoint of a
channel, socket, fifo, or eventpair.
The effects of this call on the object peer's signal bits are guaranteed to become visible before the call has completed.
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.
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 have ZX_RIGHT_SIGNAL_PEER.
Return value
zx_object_signal_peer() 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_PEER.
ZX_ERR_INVALID_ARGS clear_mask or set_mask contain bits that are not allowed.
ZX_ERR_NOT_SUPPORTED Used on an object lacking a peer.
ZX_ERR_PEER_CLOSED Called on an object with a closed peer.