The LGI$ICB_USERPARSE callback routine parses the user name
    input.

    Format

      LGI$ICB_USERPARSE  input_buffer

1  –  Returns

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

    Condition value in R0.

2  –  Argument

 input_buffer

    OpenVMS usage:character string
    type:         string descriptor
    access:       read only
    mechanism:    by reference
    The input buffer must contain the characters LOGIN in the first
    five character locations, followed by an ASCII space character
    and then the user name and applicable site-specified qualifiers.

3  –  Description

    The site can use this callback routine to parse input for
    interactive logins on character-cell and DECwindows terminals.

    Upon completion of this routine, the user name is accessible at
    the LGI$A_USERNAME entry in the standard arguments vector.

4  –  Condition Values Returned

    True (1) if successful; otherwise, any condition code returned by
    CLI$PARSE.