> GNU grep also tried very hard to set things up so that the kernel could ALSO avoid handling every byte of the input, by using mmap() instead of read() for fil

> GNU grep also tried very hard to set things up so that the kernel could ALSO avoid handling every byte of the input, by using mmap() instead of read() for file input. At the time, using read() caused most Unix versions to do extra copying. Good luck pulling this off in Chrome.