GDB

# gdb <prog-file>

# gdb –args <prog-file> <prog-args…> : start gdb with program arguments

# gdb <prog-file> <core-file> : inspect the core dump

# gdb <prog-file> <pid> : attach to the running process

# gdb –pid=<pid> –batch -ex gcore : dump the core of an alive process

run <prog-args…> (short “r”) : start the program

step [count] (short “s”) : step one line

stepi [count] (short “si”) : step one instruction

next [count] (short “n”) : step one line without entering in functions

continue (short “c”) : continue the program

finish (short “fin”) : execute until selected stack frame returns

advance [source-file]:<line> (short “adv”) : continue up to the given location

call <func-name> (short “ca”) : call a function (the context is copied so that it is not modified)

kill (short “k”) : stop the program

backtrace (short “bt”) : show the stack

frame <frame-number> (short “f”) : move to the stack drame number

list, list -, list [source-file]:<line|function> (short “l”) : show source code

thread <thread-num> (short “t”) : switch to thread

info threads (short “i th”) : show list of current threads

thread apply all bt (short “t a a bt”) : show backtraces of all threads

break [source-file]:<line|function> [thread <thread-num>] [if <condition>] (short “b”) : set a breakpoint

info breakpoints (short “i b”) : show all current breakpoints

condition <breakpoint-number> <condition> (short “cond”) : specify the breakpoint to break only if condition is true

delete breakpoints <breakpoint-number> (short “del b”, “del”) : delete a breakpoint

enable/disable <breakpoint-numbers…> (short “en” and “dis”) : enable or disable some breakpoints

print <var-name> (short “p”) : print the value/content of the variable

print *<pointer>@<nelements> : print nelements of the array

print/<format> <var-name> : print with a certain format (x for hexa, …)

display <var-name> (short “disp”) : display the value/content of the variable at every step

awatch <var-name> (short “aw”) : stops the execution whenever the variable is read or written

watch <cond-on-var> (short “wa”) : stops the execution whenever the condition on the variable becomes true

ptype <var-name> : type of variable

x <addr> : print the content of memory, can format with /<format> too

set variable <var-name> = <value> : change variable value

set $variable = <exp> : create an external variable

source <file-name> : load a set of commands from a file

You can define macros in ~/.gdbinit, eg to automatically set some breakpoints.