/*  $DOC$
 *  $FUNCNAME$
 *      UNTEXTWIN()
 *  $CATEGORY$
 *      HBCT video functions
 *  $ONELINER$
 *  $SYNTAX$
 *      UNTEXTWIN(<nTopLine>, <nLeftColumn>, <nBottomLine>, <nRightColumn>,
 *                <cReplacementCharacter|nReplacementCharacter>,
 *                [<cInitialCharacter|nInitialCharacter>],
 *                [<cEndCharacter|nEndCharacter>]) --> cNull
 *  $ARGUMENTS$
 *   <nTopLine>  Designates the line for the upper-left corner of the
 *     area.
 *   <nLeftColumn>  Designates the column for the upper-left corner of
 *     the area.
 *   <nBottomLine>  Designates the line for the bottom-right corner of
 *     the area.
 *   <nRightColumn>  Designates the line for the bottom-right column of
 *     the area.
 *   <cReplacementCharacter|nReplacementCharacter>  Replaces each
 *     character within the window, with the exception of those within the
 *     range of <cInitialCharacter|nInitialCharacter> and
 *   <cEndCharacter|nEndCharacter>.
 *   <cInitialCharacter|nInitialCharacter>  Designates the beginning of
 *     the bracketed area.  The character can be number in the range of 0 to
 *     255, or the character string type.  The default value is 176.
 *   <cEndCharacter|nEndCharacter>  Designates the end of the bracketed
 *     area.  The character can be number in the range of 0 to 255 or the
 *     character string type.  The default value is 223.
 *  $RETURNS$
 *      Returns a null string.
 *  $DESCRIPTION$
 *      Replaces an area of characters from a region of the screen
 *      TODO: add documentation
 *  $EXAMPLES$
 *  $TESTS$
 *  $STATUS$
 *      Started
 *  $COMPLIANCE$
 *  $PLATFORMS$
 *      All
 *  $FILES$
 *      Source is untext.prg, library is hbct.
 *  $SEEALSO$
 *  $END$
 */
