Using GNU Debugger (GDB) ​

To debug a C/C++ application using GDB the executable has to be compiled with the -g flag.

Start the debugger

$ gdb main

$ gdb main

Use the -q option to supress GDB's intro text

Set breakpoints with b. For, example

(gdb) b 19

(gdb) b 19

will set a breakpoint at line 43 of the source file.

Start the program in the debugger

(gdb) run

(gdb) run

Command line arguments can be provided as normal after the run command.

At breakpoints you can step into a function with step or s

(gdb) s

(gdb) s

Alternatively you can step over a function with next or n

(gdb) n

(gdb) n

You can help determine where you are in a program's execution with the backtrace or bt command

(gdb) bt

(gdb) bt

You can view the values in a program with the print or p command