just look into grep’s sources. it has loads of low-level optimizations to make string search faster. But all these optimizations work only with exact-witdth enc

just look into grep’s sources. it has loads of low-level optimizations to make string search faster. But all these optimizations work only with exact-witdth encodings, thats why it is related. P.S.: and sometimes there are a lot of problems with lower and upper-case letters http://www.gnu.org/s/grep/devel.html http://www.gnu.org/s/grep/devel.html