Shell Programming and Scripting

Hi

I am even more confused regarding this regular expression

'.*/\(.*\)\..*'

can somebody please explain that.

I tried googling on this but that did not help much

Well maybe this will help... the pieces in red are special:
'.*/\(.*\)\..*'
They define the beginning and end of a saved field. This is what will be be returned. The stuff to letf of the saved field is .*/ which matches everything up to a slash. Inside the saved field we have .* which seems to say match any characters. But we can't match literally everything, we have to save (just) enough for the rest of the expression to work. So after the saved field we have \..* which says match a dot followed by any characters.

Yes,
unfortunately ...

Hi Perderabo

Thanks for the wunderful explanation

so what i understand is
.*/ Matches upto /
\(.*\) Matches and saves myfile.cd.070505123457
\..* Match a dot followed by any characters

So shouldnt this match just cd.070505123457 and the whole expression return myfile how come it is returning myfile.cd

Thanks for being so patient with me.

regards
Hrishy

Regular expression quantifiers are greedy, so "*" means match as much as possible.

.*/ Matches any characters upto the last /
\(.*\)\. Matches and returns any characters upto the last .
.* not actually required. (I originally thought that this was required because expr regular expressions are anchored, but it turns out that they are only achored to the start of the expression.)

Hi Ygor

Thanks ..a million i got it.

Gotta remember this "regular expressions are greedy "

regards
Hrishy