Question

I need to print some structure for debugging purposes.Since the code base is huge i am having difficulty locating the exact member I need to look into.Is there some way I could print out the entire structure? or atleast know what type of structure it is so that I can go back and look into it’s definition?

Answer 1

Use a debugger. Most debuggers give you an option to see the contents of an entire structure whenever you hit a breakpoint. On *nix the most popular debugger is gdb, and on Windows the most popular IDE (which includes a debugger) is Visual Studio. Both the sited I linked to have free-as-in-beer download links.

In gdb, you can set a breakpoint with the break command, and once you reach the breakpoint you can print the contents of the struct with the print command. More specifically, you can compile with debugging data included (the -g flag in gcc), and then use

$ gdb debugging_executable
Some basic information about GDB gets printed here
> break main.c:100
> run
> print struct_variable

It’s also worth looking into the step and continue commands.

In Visual Studio, you can set a breakpoint by double-clicking just to the left of the source line (there is a gray bar on the left side of the editor), and mouse over the variable name to inspect the contents once you reach the breakpoint.