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cdebugginggdbheap-memorystack-memory

how to use gdb to explore the stack/heap?

Could anyone please give me a quick overview/point me to documentation of a way to inspect the stack (and heap?) of a C program? I thought this should be done with GDB, but if there are other more straighforward alternatives, then that should be fine as well.

Thanks.

Solution

  • My first approach to using GDB for debugging is to setup breakpoints. This is done like so:

    prompt> gdb ./x_bstree.c
(gdb) #prompt
(gdb) b 123 #break at line 123
(gdb) r #start program

    Now your program halts at line 123 of your program. Now you can examine variables in stack or heap using print. For stack variables just use print <varname>. For heap variables (pointers) use print <*varname>. Not sure there is anything special to do for examining stack/heap variables?

    Of course to debug multi-threaded applications you would need to make it run in single-threaded mode & then dubug Otherwise it becomes difficult to predict what's happening.

    For anything else there is extensive documentation of gdb & many sites also provide gdb cheat sheets.