Reverse engineering

ltrace ./<programm> runs the specified command until it exits, intercepts and records the dynamic library calls which are called by the executed process and the signals which are received by that process
faketime '2008-12-24 08:15:42' if you need to invoke your program with a set time
dismangle Function c++filt for C++ functions starting with _Z

If your terminal bugs use CTRL + L to reprint
Start with Text User Interface gdb -q -tui <program>
Set the Layout to ASM layout asm and set disassembly-flavor intel
Disassemble function with disassemble <main>
Set a breakpoint b <function name>, b <line>, to remove breakpoint disable <breakpoint number>, tb is a temporary breakpoint only works one time
Run the program run
Starts the program and stops at main start
c or continue resumes execution until the next breakpoint is reached.
Next only goes to the next line n also known as "step over"
Step to the next instruction s also known as "step into"
Similarly ni and si for next instruction and step instruction for single ASM instruction stepping
Backtrace back
Go to frame X: f X, e.g. f 1 goes to frame 1 (i.e. to the caller of the current function)
show all registers info register or i r
show a specific register using i r rax
evaluate a C expression using p <expression>, e.g. p (char *)0xffff7d08 or p someVariable[13] or p (char *)$rax
'gdb -p ' to look at programs with a while loop (find pid with 'ps ax')