Re: Debugging C program strings with STRDBG

Hello Stephen,

Am 03.09.2025 um 22:48 schrieb Stephen West via C400-L <c400-l@xxxxxxxxxxxxxxxxxx>:

There are syntax differences in a STRDBG session of a C or C++ program.
On the 'eval' statement of your session, try the following statement:

EVAL **dataarea:c 30

This will work if dataarea is a pointer.

The ** dereferences the pointer to get at the memory it points to.

Yields CPF7E18 => ID no not a pointer.

The :c tells is to display the memory as a character. (Try :x for hex as an alternative) Tip: Characters in C/C++ are null terminated. They will end with x'00', so the :x way of viewing the data lets you see the null terminators.

Thanks! Might help indeed!

The 30 is just the number of characters in memory that you want to display. Nothing magical to 30.

If dataarea is a pointer to an array, try the following syntax:

EVAL *dataarea[1]:c 50

The [1] indicates that I want to view the 2nd array element (arrays start with zero in C/C++).

Thanks! So, in the end, I found

EVAL *dataarea:c 20

to eventually reveal the string in the memory area. (It's declared as follows:

char dataarea[] = "HTTPPROXY QUSRSYS ";

)

From there, I'm now able to see that the memory area to be filled with the *DTTARA content by the QWCRDTAA API contains junk. More testing…

Thanks a lot, that helped tremendously!!

:wq! PoC