Object-oriented Programming in C++

Surviving with GDB

If you are a Mac user, you have to use lldb instead of gdb. You can find the basic commands on this page. For the Linux and Windows/WSL users, you can use the commands provided here.

The commands every padawan should know

Launching GDB (in the terminal)
gdb [prog]	Loads the program [prog] into GDB.
gdb --args [prog] [arg1 arg2 ...]	Loads the program [prog] into GDB with the parameters [arg1 arg2 ...]
gdb [prog] [core-file]	Loads the core dump of the program [prog] into GDB.
q or quit	Quits GDB.
Showing the code (in gdb)
layout src	Splits the view and shows the code.
Starting Program Execution (in gdb)
r or run	Starts the execution of the program loaded in GDB.
r [arg1 arg2 ...]	Starts the execution of the program loaded in GDB with the parameters [arg1 arg2 ...].
set [args arg1 arg2 ...]	Sets the list of arguments ([arg1 arg2 ...]) for the next program to start.
Examining the State of a Process (in gdb)
p [var] or print [var]	Displays the value of the variable [var].
p/x [var]	Displays the hexadecimal value of the variable [var].
display [var]	Displays the value of the variable [var] at every stop of the program.
bt or backtrace	Displays the call stack.
frame	Displays the current call frame.
frame [x]	Selects the call frame [x].
l or list	Displays the code around the selected call frame.
Monitoring Process Execution (in gdb)
b [pos] or break [pos]	Sets a breakpoint at [pos]. [pos] can be a function name, a line number (from the current file), a file name+line number (break my_file:57), etc.
clear [pos]	Removes the breakpoint at [pos].
d [num] or delete [num]	Removes the breakpoint number [num].
w [var] or watch [var]	Watches the state of the variable [var].
Controlling Process Execution (in gdb)
n or next	Steps forward one line.
s or step	Steps forward one line. If the instruction to execute is a function call, it does not descend into the function.
c or continue	Continues execution until the next breakpoint.

Becoming a GDB Jedi Master

Assembler (in gdb)
disassemble [function]	Displays the assembly code of the function [function].
info registers	Displays the values of the registers.
p $[register]	Displays the value of a register. Example: print $eax.
Reverse Debugging (in gdb)
record	Starts recording the process behavior.
record stop	Stops the recording.
rs or reverse-step	Like step, but backwards.
rn or reverse-next	Like next, but backwards.
rc or reverse-continue	Like continue, but backwards.
set can-use-hw-watchpoints 0	Allows using watchpoints in reverse debugging.
Others (in gdb)
break [pos] if [cond]	Stops the process at [pos] if the condition [cond] is met.
up	Moves up one call frame in the stack.
down	Moves down one call frame in the stack.
attach [pid]	Attaches GDB to the process with pid [pid].
detach	Detaches the process from GDB.
set env [var]=[value]	Sets the value [value] to the environment variable [var].

Object-oriented Programming in C++

Surviving with GDB

The commands every padawan should know

Launching GDB (in the terminal)

Showing the code (in gdb)

Starting Program Execution (in gdb)

Examining the State of a Process (in gdb)

Monitoring Process Execution (in gdb)

Controlling Process Execution (in gdb)

Becoming a GDB Jedi Master

Assembler (in gdb)

Reverse Debugging (in gdb)

Others (in gdb)

Other Resources