INT 21 u - European MSDOS 4.0 - "PRUN" - UNBLOCK A PROCESS
AH = 9Ah
DS:BX -> memory location processes may have blocked on
Return: AX = number of processes awakened
ZF set if no processes awakened
Desc:   restart all processes waiting for the specified "restart" signal
SeeAlso: INT 2F/AX=0802h

See also: 2199

219A - European MSDOS 4.0 - "PRUN" - UNBLOCK A PROCESS