A backtrace is a summary of how the program got where it is. It shows one line per frame, for many frames, starting with the currently executing frame (frame zero), followed by its caller (frame one), and on up the stack. `backtracÚ `bt' Print a backtrace of the entire stack: one line per frame for all frames in the stack. You can stop the backtrace at any time by typing the system interrupt character, normally `Control-C'. `backtrace N' `bt N' Similar, but stop after N frames. Each line in a backtrace shows the frame number, the program counter, the function and its arguments, and the source file name and line number (if known). The program counter is omitted if is the beginning of the code for the source line. This is the same as the first of the two lines printed when you select a frame.