
DATEINPUT accepts and verifies date input in a Reverse
Video entry panel, all the usual editing keys are
supported and entry is terminated by either a Carriage
Return or one of several special function keys:


Return Codes:   

1  =  <Escape>    abort entry returning a null string
2  =  <F2>        repeat previous entry for this field
3  =  <Up Arr>    pressed, move to previous field 
4  =  <Dn Arr>    pressed, move to next field
5  =  <Pg Up>     pressed, move to top of screen
6  =  <Pg Dn>     pressed, move to end of screen


Editing keys:

<L.Arrow>   =  Move cursor one character to the left
<R.Arrow>   =  Move cursor one character to the right
<Home>      =  Move cursor to first character of field
<End>       =  Move cursor to last character of field
<Ctrl End>  =  Clear from current cursor position to
               the end of the entry field.
<Insert>    =  Toggle between Insert and Overtype.
<Delete>    =  Delete character under the cursor.
<BackSpace> =  Replace character under cursor with a
               blank space and move the cursor one
               character to the left.
<F1>        =  pop up on-line HELP screen.




DATEINPUT is also designed to be part of a full-screen
data-entry system. Your program can examine the return
code to determine whether the operator just wishes to
terminate entry or move forwards or backwards between
entry fields.

See also the REVINPUT function for a similar, more
general-purpose, data-entry routine.
