Unix regular expression

[Jake.]

Anyone know how I would select a range files by numbers in the filenames?

(Simplified) I'm trying to select all files in a directory that have _39_ or _40_ in the name.
I've tried things like

 ls *_[3,4][9,0]_*

but that also selects other files, like ones with _30_ in their name.


I know I could do it other ways, like ls *_[39_* *_40_*

but it's the regular expression part I'm trying to understand.



Thanks for any pointers.

[guffhoover]

Only did Linux once in Uni many years ago but would the grep command do anything for you?

[cs02rm0]

Not sure you can do regexps with ls, just wildcards, would be happy to be corrected there though. You can use regexps with grep as suggested.

ls|grep "_39_\|_40_"

Edited by cs02rm0 on Saturday 23 January 22:03

[ewenm]

I think ^^^^^ is right - you'll need to pipe the ls output to another expression to use the filters. If you can, get hold of a copy of Unix in a Nutshell - very useful tome. I think I once found an online version, but can't locate it easily now.

[Jake.]

Very interesting guys - thanks. I wasn't really expecting any replys at this time on a Saturday.

cs02rm0 said:

Not sure you can do regexps with ls, just wildcards, would be happy to be corrected there though. You can use regexps with grep as suggested.

ls|grep "_39_\|_40_"

I'm pretty sure regexps work with ls (only some maybe?) because
ls *_[3,4][9,0]_* does work (it works wrong for what I want but it's a regexp, isn't it?

Cheers






ps,
Any idea why I cant do more than one {{{ code tag in a post? Try it, very odd.

[grumbledoak]

No regexps for ls - you get the shell's wildcard expansion (the absence of quotes is a bit of a clue).

[Jake.]

OK then I'll give

_39_\|_40_

a try tomorrow then.

Thanks all, much appreciated.

[cyberface]

Jake. said:

Any idea why I cant do more than one {{{ code tag in a post? Try it, very odd.

That's a well known problem in the PH forum code that hasn't been fixed and it's been outstanding for ages.

There are lots of other bugs in the PH forum code too... but I won't divulge them because I like to still be able to own the forum if I want

The inability to do two code blocks in one post is *very* irritating though... however since it's probably only an issue for the Computers & Stuff forum, it's probably not high on the list of priorities, sadly...

[dcb]

Jake. said:

(Simplified) I'm trying to select all files in a directory that have _39_ or _40_ in the name.

ls -1 | egrep "_39_|_40_"

If you need further help, man egrep has all the detail.

[TooLateForAName]

Jake. said:

(Simplified) I'm trying to select all files in a directory that have _39_ or _40_ in the name.
I've tried things like

 ls *_[3,4][9,0]_*

it's the regular expression part I'm trying to understand.

The unix in a nutshell book is very good. I remember starting a project with a bunch of people who were all mainframe/mini people and none of them had a clue about unix. I bought a case of unix in a nutshell, went down very well.

There is also a regex book but probably you don't need the complexity.
Basically the square brackets matches a single character so as you've found you match a 3 or a 4 followed by a 9 or a 0 hence 39,30,49,40.

Depending on what you are tyring to do you might want to have a look at sed and awk which are very handy little utilities.