Q40494: Watching Pointers in QuickC Debugger

Article: Q40494
Product(s): See article
Version(s): 1.00 1.01 2.00
Operating System(s): MS-DOS
Keyword(s): ENDUSER | | mspl13_c
Last Modified: 20-JAN-1989

The QuickC debugger makes a distinction between pointers of type CHAR
and all other types. The debugger will assume that any "char *"
pointer will contain the address of a Null terminated string.

The impact of this assumption can be seen when setting a WATCH VALUE
on a specified pointer. If the pointer is declared as "char *", then
the debugger displays the WATCH value as the string that is pointed to
by the pointer. If the pointer is declared as any type other than
"char *", then the WATCH value displays the address of the variable
and not the value of the variable.

The following code fragments illustrate this distinction:

char *CHptr = "Faust liebt Gretchen" ;
int  *INTptr= "Faust liebt Gretchen" ;

A WATCH set on CHptr displays the following:

   "Faust liebt Gretchen"

A WATCH set on INTptr displays the address of the string and not the
string itself:

   'Faust liebt Gretchen'

If you want to WATCH the string pointed to by INTptr, do the
following:

1. Pull down the DEBUG menu.

2. Choose the WATCH VALUE selection.

3. Type "(char *)INTptr".

Casting INTptr to "char *" type displays the character string.

If you want to WATCH the address of the string to which CHptr points,
do the following:

1. Pull down the DEBUG menu.

2. Choose WATCH VALUE.

3. Type "(int *)CHptr".

Casting CHptr to a type other than "char *" (such as "int *")
displays the address of the string to which CHptr points.

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