[TUHS] Short history of 'grep'

Dave Horsfall dave at horsfall.org
Sat Mar 5 11:48:19 AEST 2016

On Sun, 31 Jan 2016, Doug McIlroy wrote:


> That's the short story. In real life egrep overcomes the exponential by 
> lazily constructing the machine--not generating a state until it is 
> encountered in the parse, so no more than n states get constructed. It's 
> a complex program, though, for the already fancy preprocessing must be 
> interleaved with the parsing.

Many thanks; I think I understand a little better now...  It's been many 
years since I majored in Computer Science :-)

Dave Horsfall DTM (VK2KFU)  "Those who don't understand security will suffer."

More information about the TUHS mailing list