Assign_CharHook


Purpose   Identifies a procedure that will be called every time the user
          presses a key during field input.

Decln.    Assign_CharHook(Proc:Char_Hook_Proc);

Remarks   Proc is the name of the procedure to Hook into the IO routines.
          The procedure must be declared far with 3 passed parameters; a
          variable type char, a variable type ID and a variable type byte.
          The procedure will be passed the character that was just pressed,
          the current field ID number and a refresh code.

Example

    {$F+}
    PROCEDURE BOBS_HOOK(VAR C:CHAR;VAR ID:BYTE;VAR R:BYTE);
    BEGIN
        IF C = F2 THEN
           DISPLAY_USERID;
    END;
    {$F-}

BEGIN
    ASSIGN_CHARHOOK(BOBS_HOOK);
END;

This procedure is only available for Turbo 5.0 programmers. Turbo 4.0
programmers should replace the procedure with the statement:

     IO_CHARHOOK := @BOBS_HOOK;