Using GDB

GDB (project, documentation) is a simple debugging tool for GNU command line systems.

You can Google around for lots of information about it. A short tutorial, a longer tutorial, and a reference card are pretty easy to find.

For GDB to be most effective, you should compile your code with the -g flag to leave debugging symbols in your executable. This will do things like leave variable names and line numbers in the executable so that GDB can show you what/were things are.

The commands that you will use the most are:

help

r arguments (run)

r 5

file executable

bt (backtrace)

p expression (print)

p argv[1]

b file:symbol (breakpoint)

b main.c:5

b main.c:parseArgs

d (delete breakpoints)

s (step) [step-into]

n (next) [step-over]

c (continue)

up

q (quit)