Retrieve a handle to a system event.
#include <zircon/syscalls.h> zx_status_t zx_system_get_event(zx_handle_t root_job, uint32_t kind, zx_handle_t* event);
root_job must be a handle to the root job of the system with the MANAGE_PROCESS right.
The only valid value for kind is ZX_SYSTEM_EVENT_LOW_MEMORY.
When kind is ZX_SYSTEM_EVENT_LOW_MEMORY, an event will be returned that will assert ZX_EVENT_SIGNALED when the system is nearing an out-of-memory situation. A process that is waiting on this event must quickly perform any important shutdown work. It is unspecified how much memory is available at the time this event is signaled, and unspecified how long the waiting process has to act before the kernel starts terminating processes or starting a full system reboot.
None.
zx_system_get_event()
returns ZX_OK on success, and event will be a valid handle, or an error code from below on failure.
ZX_ERR_ACCESS_DENIED The calling process' policy was invalid, the handle root_job did not have ZX_RIGHT_MANAGE_PROCESS rights, root_job was not the root job of the system.
ZX_ERR_INVALID_ARGS kind was not ZX_SYSTEM_EVENT_LOW_MEMORY.