299 ;;Quote: bdb bidirectional debugger with re-execution instead of history-logging; backwards counterparts of step, continue, next, finish, until, and undo

300 ;;Quote: gdb debugger executes one million processor cycles for each trap/resume; context switches and system calls

300 ;;Quote: practical re-execution of programs with 64-bit counters and periodic checkpoints; less than 100% overhead

300 ;;Quote: re-execute system calls by logging and replaying return values

301 ;;Quote: bdb limits the step points of a program; prevents stepping into library routines

301 ;;Quote: two-pass implementation of bcontinue; first reexecution pass establishes the breakpoint count up to the current position; second pass goes to the nth breakpoint

302 ;;Quote: previous reexecution is not the inverse of next; two-pass algorithm

303 ;;Quote: finish/before go to function exit/entrance; two-pass algorithm

304 ;;Quote: buntil goes to last step point satisfying a condition; useful; two-pass algorithm

304 ;;Quote: bdb adds step points before and after functional expressions

306 ;;Quote: checkpoints by fork every 1/10 second and thinning of old checkpoints

308 ;;Quote: fast undo by always retaining the checkpoint prior to last breakpoint

308 ;;Quote: implemented system call replay for 35 of 262 Unix system calls