Provides a process with an I/O channel so input/output operations
    can be performed on a device, or establishes a logical link with
    a remote node on a network.

    On Alpha and Integrity server systems, this service accepts 64-
    bit addresses.

    Format

      SYS$ASSIGN  devnam ,chan ,[acmode] ,[mbxnam] ,[flags]

    C Prototype

      int sys$assign  (void *devnam, unsigned short int *chan,

                      unsigned int acmode, void *mbxnam,...);