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Debugging with GDB

After reading "Debugging with GDB" by RMS I've made this reference sheet, since I rarely program in Linux I've excluded everything Linux specific:
General Usage
file a.out Load the program a.out
symbol-file symbol Load symbol file symbol
run Run program
continue Execute program until the next breakpoint
print i Print variable i
print i=3 Change variable i to 3
x 0x200 Print value at 0x200
break printf Set breakpoint at function printf
info breakpoints List breakpoints
delete 2 Delete breakpoint 2
delete Delete all breakpoints
info locals Show variables in stack
backtrace Show stack
info frame stack info
list + Show sourcecode before last printed
list - Show sourcecode before last printed
list func Show sourcecode around function name func
list 30 Show sourcecode around line 30
info line func Get start and end memory addresses of function func
info line 30 Get start and end memory addresses of section around line 30
disassemble 0x300 0x400 Disassemble between memory addresses 0x300 and 0x400
info registers Display registers
info all-registers Display all registers
set $rax = 0x5 Set register rax to 0x5
info symbol printf shows memory location of printf
info address printf Shows section of printf
whatis printf Gives data type of symbol
ptype /o struct exstruct Gives layout and offsets of the struct exstruct
info scope printf Show variables within scope of function printf
info functions Print all defined functions
info variables Print all defined variables
jump func Jump to function func
return 0 Force function to return 0
set $pc-= 1 Effectively goes back one instruction
signal 9 Resume program and send sigkill
Display
layout src Displays Source window
layout asm Displays disassembly window
layout split Displays source and disassembly windows
layout regs Displays register window
set disassembly-flavor intel Set preferred assembly syntax
OS Development
set architecture i8086 For debugging x86 bootloader code
set architecture i8086 For debugging x86 bootloader code
set architecture i386:x86-64 For debugging AMD64 code
target remote localhost:26000 For connecting to $ qemu-system-x86_64 -gdb tcp::26000 ...