The Call Routine with General Argument List routine calls a
    routine with an argument list specified as an array of longwords,
    the first of which is a count of the remaining longwords.
    LIB$CALLG is a callable version of the VAX CALLG instruction.

    Format

      LIB$CALLG  argument-list ,user-procedure

1  –  Returns

    OpenVMS usage:longword_unsigned
    type:         longword (unsigned)
    access:       write only
    mechanism:    by value

    Return value, if any, of the called routine, unchanged by
    LIB$CALLG.

2  –  Arguments

 argument-list

    OpenVMS usage:arg_list
    type:         unspecified
    access:       read only
    mechanism:    by reference, array reference

    Argument list to be passed to user-procedure. The argument-
    list argument is the address of an array of longwords that is
    the argument list. The first longword contains the count of the
    remaining longwords, to a maximum of 255.

 user-procedure

    OpenVMS usage:procedure
    type:         procedure value
    access:       function call (before return)
    mechanism:    by value

    Routine that LIB$CALLG calls with the specified argument list.