[The most useful cheat sheets are those with the second-rate commands you don't use all the time!] Some keywords have explicit abbreviations (e.g. backtrace → bt), but one can also make use of implicit abbreviations (cut-offs) (e.g. backtrace → ba) and substitutions (e.g. off → 0).

• Break on syscall:
  b openat (breakpoint on libc function)
  catch syscall openat (actual syscall)
• Break on C++ exception:
  catch throw
• Backtrace everything:
  thread apply all bt
• Produce backtrace from command-line:
  gdb -p 12345 -ex 'thread apply all bt' -ex quit >xyz.txt
gdb /usr/bin/prog core.file -ex 'thread apply all bt' -ex quit >xyz.txt
  
• Figure out thread number from PID:
  thread find 12345
• Show register file:
  info registers, info all-registers
• Show loaded libraries etc.:
  info proc mappings
• Print C++ object vtable (of size N entires) in gdb: p/a (*(void ***)this)[0]@N
• Dump memory region to file (start–end, not start+length):
  dump binary memory output.bin 0x50000 0x60000
• Disable notifications about petty signals:
  handle SIGTSTP nostop noprint
• Disable paging/page infinitely:
  set pagination off
set height 0
• Disable wrapping:
  set width 0
• Disable colors:
  set styling enable off
• Disable smart view of objects:
  disable pretty-printer

This subpage was last modified 2026-01-20 by ej • contact