Gnu Debugger (GDB)
GDB is a tool for debugging programs. It consists of a server and a
client. The GDB server runs, controls, and monitors the debugged
program. The client can send commands such as setting breakpoints or
performing single instruction steps.
Usage
- compile your binary with the gcc debug option
-g
- start gdb with your binary
gdb BINARY
- set a breakpoint
b main.c:12
- run the program
run
- on break: inspect variables with
p myvar
Commands
| Usage |
Description |
b file:line |
set breakpoint in file at line |
run [arglist] |
start your program [with arglist] |
p expr |
display the value of an expression |
i command |
display info for command, e.g. i b |
| Program Flow |
Short |
Description |
continue |
c |
continiues program execution |
next |
n |
execute one line of code (step over) |
step |
s |
execute a single instruction (step into) |
finish |
|
executes the current subprogram (step out) |
| Stack |
Description |
bt |
print backtrace |
frame |
display current frame |
up |
move one frame up |
down |
move one frame down |
References