cs_id

    OpenVMS usage:identifier
    type:         longword integer (unsigned)
    access:       read only
    mechanism:    by reference
    Address of a longword that NCS uses to identify a collating
    sequence. The cs_id argument is required and can be obtained
    by a call to the NCS$GET_CS routine.

    All calls to the NCS$COMPARE routine and the call to the NCS$END_
    CS routine that terminates the comparison must pass this longword
    identifier. Upon completion, the NCS$END_CS routine releases the
    memory used to store the collating sequence and sets the value of
    the longword identifier to 0.

 string_1

    OpenVMS usage:char_string
    type:         character string
    access:       read only
    mechanism:    by descriptor
    Descriptor (length and address) of the first string.

 string_2

    OpenVMS usage:char_string
    type:         character string
    access:       read only
    mechanism:    by descriptor
    Descriptor of the second string.