A SRV_ATTENTION event handler is the only event handler that runs at interrupt level. An Open Server application can only issue the following Server-Library calls from inside a SRV_ATTENTION handler:
srv_wakeup with the wakeflags argument set to SRV_M_WAKE_INTR
srv_ucwakeup with the wakeflags argument set to SRV_M_WAKE_INTR
srv_thread_props with the cmd argument set to CS_GET
srv_props with the cmd argument set to CS_GET
srv_event_deferred
No other Server-Library routines can be called from the SRV_ATTENTION event handler, or from other interrupt-level code.