INT 21 - Novell NetWare - SYNCHRONIZATION SERVICES - OPEN SEMAPHORE
AX = C500h
DS:DX -> semaphore name (counted string, max 127 bytes)
CL = initial value for semaphore
Return: AL = status
00h successful
BL = number of processes having semaphore open
CX:DX = semaphore handle
FEh invalid name length
FFh invalid semaphore value
Notes:  this function is supported by NetWare 4.6+, Advanced NetWare 1.0+, and
Alloy NTNX
the semaphore's value is incremented by AX=C503h and decremented by
AX=C502h
SeeAlso: AX=C502h,AX=C503h,AX=C504h

See also: 21C501

21C500 - Novell NetWare - SYNCHRONIZATION SERVICES - OPEN SEMAPHORE