The Erase Column from Display routine erases the specified
    portion of the virtual display from the given position to the
    end of the column.

    Format

      SMG$ERASE_COLUMN  display-id [,start-row] [,column-number]

                        [,end-row]

1  –  Returns

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

2  –  Arguments

 display-id

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

    Identifier of the virtual display to be affected. The display-id
    argument is the address of an unsigned longword containing this
    virtual display identifier.

 start-row

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

    Optional line number at which the erase operation begins. The
    start-row argument is the address of a signed longword that
    contains the specified line number. If this argument is omitted,
    the column-number argument is ignored and the erase operation
    begins at the current location of the virtual cursor for that
    virtual display.

 column-number

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

    Optional column number at which the erase operation begins.
    The column-number argument is the address of a signed longword
    that contains the specified column number. If this argument
    is omitted, the start-row argument is ignored and the erase
    operation begins at the current location of the virtual cursor
    for that virtual display.

 end-row

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

    Optional row number at which the erase operation ends. The end-
    row argument is the address of a signed longword that contains
    the specified row number.