I’m not a big GDB guy, but Google always helps:

• Create a textfile with the following content:

  set height 0
  thread apply all bt
  detach
  quit

• Run the following command:

  gdb $EXE -pid $PID -command $TEXTFILE > $OUTPUTFILE

  where:

  • $EXE is the path to the executable
  • $PID is the PID it is running under
  • $TEXTFILE is the file where your’ve saved the previous commands
  • $OUTPUTFILE is the file where you would like your stackdump to be saved.

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