Grep for search, but what for replace?

TheSpecial · 04-12-2003, 08:09 AM

Hi,

I want a tool just like grep (which finds a string in several files), but this should replace a string I specify by another, is there such a program?

Thanks!

unSpawn · 04-12-2003, 08:23 AM

If you don't want to script grep+sed, then check laffeycomputer.com for "rpl".

cuckoopint · 04-12-2003, 06:27 PM

sed or pearl

; )

m0rl0ck · 04-12-2003, 07:01 PM

perl -p -i -e 's/this/that/g' filename

At the commandline will replace "this" with "that" in filename.
filename coul be *.html or * or whatever.

TheSpecial · 04-13-2003, 02:19 AM

Thx for the information!!

TheSpecial · 04-24-2003, 02:35 PM

Oki, I tried it out, but I got onto a problem...

I execute:
perl -p -i -e "s#\$ENV\{\'DOCUMENT_ROOT\'\}#\"/home/kenny/public_html/\"#" *.cgi

And the file now contains (instead of $ENV{'DOCUMENT_ROOT'})$ENV"/home/kenny/public_html/", how can I get rid of the $ENV? I tought that \$ should skip it?

Also another question, is it possible to search recursivly in the subdirectorys?

Thanks!
Kenny

BigNate · 04-24-2003, 04:13 PM

grep takes the -r (recursive option)

man grep for details

acid_kewpie · 04-24-2003, 04:18 PM

using perl is quite pointless i'd say... the same regex should work fine with sed.

GAVollink · 04-24-2003, 04:28 PM

find . -name "*.cgi" -exec perl -p -i -e 's/this/that/g' {} \;

As far as your environment variable switch-out - I can't tell what you were trying to change, and what you were trying to change it to. I'd be more helpful otherwise.

(I think perl can do this better when coupled with find - but I am probably not aware of some flag that would ask 'sed' to read from a file instead of a stream)

cuckoopint · 04-24-2003, 07:43 PM

Quote:

but I am probably not aware of some flag that would ask 'sed' to read from a file instead of a stream

Do you mean like:

Code:

sed [OPTION]... {script-only-if-no-other-script} [input-file]...

arnold · 04-24-2003, 07:57 PM

i favor ex with here script
ex *.cgi<<!
%s/this/that/g
%s/abc/def/g
w
q
!

PS no matter which way, u must test and backup files b4 making a production run

m0rl0ck · 04-24-2003, 08:01 PM

Quote:

how can I get rid of the $ENV? I tought that \$ should skip it?

I just tried:
perl -p -i -e 's/\$ENV//g
on a test file and it worked great.

m0rl0ck · 04-24-2003, 08:15 PM

Quote:

using perl is quite pointless i'd say... the same regex should work fine with sed.

Yeah, "sed -e 's/this/that/g' filename" works great.
I'm afraid this may be a case of "if the only tool you have is a hammer" Im used to using perl as a first resort to solve just about any system/admin problem. Its probably a failing, but perl is such a darn good hammer

arnold · 04-25-2003, 07:29 AM

sed is "stream editor", not file editor. If you want to directly modify a file, you need perl or ex.

perl and ex can do the job in 1 command, sed requires at least 2 commands - sLedGE hammer

m0rl0ck · 04-25-2003, 10:57 PM

Quote:

perl and ex can do the job in 1 command, sed requires at least 2 commands

But "sed -e 's/this/that/g' *" gives exactly the same result as the perl one liner and its fewer characters.