Q68696: "?CANNOT DISPLAY" After Column 135 in Command Window

Article: Q68696
Product(s): See article
Version(s): 3.00 3.11 | 3.00 3.11 3.50
Operating System(s): MS-DOS | OS/2
Keyword(s): ENDUSER | | mspl13_basic
Last Modified: 6-FEB-1991

The code below demonstrates a limitation of the CodeView debugger.
When the command "?y" is executed in the COMMAND window, the structure
"y" is displayed. However, CodeView displays the structure only to
column 135 and then prints "?CANNOT DISPLAY," ignoring the rest of the
elements in the structure. The output appears as follows:

   --------------------------command----------------------------
  |>?y                                                          |
  |{this_field_01=0x0000, ... ,this_field_07=?CANNOT DISPLAY    |
  |                        ^                 ^                  |
  |                        |                 |                  |
  |                  Fields 2-6 displayed    Column 135         |
  |                                                             |
   -------------------------------------------------------------

                      CodeView Command Window

To view all elements of a structure, you should use the QUICK WATCH
function. In the example below, the contents of the whole structure
can be seen by typing "??y". A dialog box will appear on the screen
showing the contents of the structure. By scrolling down in the dialog
box, the contents of every element of the structure can be seen. The
structure contents are displayed as follows:

          --------------- Quick Watch -----------------
         |                                             |
         |-y                                           |
         |   this_field_01=0                           |
         |   this_field_02=0                           |
         |   this_field_03=0                           |
         |   this_field_04=0                           |
         |   this_field_05=0                           |
         |   this_field_06=0                           |
         |   this_field_07=0                           |
         |   this_field_08=0                           |
         |   this_field_09=0                           |
         |   this_field_10=0                           |
         |   this_field_11=0                           |
         |   this_field_12=0                           |
         |   this_field_13=0                           |
         |   this_field_14=0                           |
         |   this_field_15=0                           |
          ---------------------------------------------

                      Quick Watch of Variable

Sample Code
-----------

struct x {
   int this_field_01;
   int this_field_02;
   int this_field_03;
   int this_field_04;
   int this_field_05;
   int this_field_06;
   int this_field_07;
   int this_field_08;
   int this_field_09;
   int this_field_10;
   int this_field_11;
   int this_field_12;
   int this_field_14;
   int this_field_15;
   int this_field_16;
   int this_field_17;
   int this_field_18;
   int this_field_19;
   int this_field_20;
};

main()
{
    struct x y;
}

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