The Insert Key in Cross-Reference Table routine inserts
    information about a key into a cross-reference table.

    Format

      LIB$CRF_INS_KEY  control-table ,key-string ,symbol-value ,flags

1  –  Returns

    None.

2  –  Arguments

 control-table

    OpenVMS usage:vector_longword_signed
    type:         longword integer (signed)
    access:       read only
    mechanism:    by reference, array reference

    Cross-reference table into which LIB$CRF_INS_KEY inserts
    information about the key. The control-table argument is the
    address of a signed longword integer pointing to the cross-
    reference table. You must name this table each time you call a
    cross-reference routine because you can accumulate information
    for more than one cross-reference table at a time.

 key-string

    OpenVMS usage:char_string
    type:         character string
    access:       read only
    mechanism:    by descriptor

    A counted ASCII string that contains a symbol name or an unsigned
    binary longword. The key-string argument is the address of a
    descriptor pointing to the key.

 symbol-value

    OpenVMS usage:longword_signed
    type:         longword integer (signed)
    access:       read only
    mechanism:    by reference

    Symbol value, the address of which LIB$CRF_INS_KEY inserts in the
    cross-reference table. The symbol-value argument is the address
    of a signed longword integer containing this value. Both the key
    and value addresses must be permanent addresses in the user's
    symbol table.

 flags

    OpenVMS usage:mask_longword
    type:         longword (unsigned)
    access:       read only
    mechanism:    by reference

    Value used in selecting the contents of the KEY2 and VAL2 fields;
    flags is stored with the entry. The flags argument is the address
    of an unsigned longword containing the flags. When preparing the
    output line, LIB$CRF_OUTPUT uses flags and the 16-bit mask in the
    field descriptor table to extract the data. The high-order bit of
    the word is reserved for LIB$CRF_INS_KEY.