Perl Oneliner: Recursive Search and Replace

wouldn’t it be better to pipe the “find” output to xargs and pass this to the perl expression?

Klaus is right because the find clause might produce enough output that it will reach the limit for line length (input too long). Remarkably, this happens frequently enough. I remember having to debug somebody’s perl script that was written to search through 750gb of text files. One day, the number just managed to hit the max and it errored out with “input too long” messages.

find . | xargs perl -p -i -e ‘s/something/else/g’

However, for smaller directories, I really like your second solution, grepping good matches out first. You should run some time trials to see if it’s a speed win to have grep do the detection and then only perl the ones you need. I bet there’s a break-even where less than some percentage of relevant files will give you a speed advantage.

-Josh-

Just one more way to do:

find ./ -exec perl -p -i -e ‘s/faltoo_string/aur_bhi_faltoo_string/g’ {} ;

Hey guys, be careful with your symlinks! I used Nics method from post number 2, and it converted my symlink files to real files. That ended up breaking some stuff for me.

I tried all these examples to no avail using Solaris9, just trying to find all files in filesystem with *.zip and change it to *.ZIP.

# perl -v

This is perl, v5.6.1 built for sun4-solaris-64int
(with 48 registered patches, see perl -V for more detail)

# find /usr/local/tmp/aaa -name “*.zip” -exec perl -p -i -e ‘s/zip/ZIP/g’ {} ;

# ls -l /usr/local/tmp/aaa
total 6
-rw-r–r– 1 carlos staff 49 Feb 22 09:35 9_Recommended.zip
-rw-r–r– 1 carlos staff 49 Feb 22 09:35 DLG_V11_2.zip
-rw-r–r– 1 carlos staff 49 Feb 22 09:35 tzupdater-1_0_1.zip
#

Single quotes doesn’t work too

# find /usr/local/tmp/aaa -name ‘*.zip’ -exec perl -p -i -e ‘s/zip/ZIP/g’ {} ;
# ls -l /usr/local/tmp/aaa
total 6
-rw-r–r– 1 carlos staff 49 Feb 22 09:37 9_Recommended.zip
-rw-r–r– 1 carlos staff 49 Feb 22 09:37 DLG_V11_2.zip
-rw-r–r– 1 carlos staff 49 Feb 22 09:37 tzupdater-1_0_1.zip

Hey There,

For “not replacing” files that already exist, I use this with that perl one-liner when I’m piping filenames to it – it’s not built into the options, but is pretty simple to type once 🙂

perl -p -i -e ‘s/ThisThing/ThatThing/; rename $_, unless -e $_;’

It doesn’t work “out of context” because $_ requires a value, but you can use the rename half of my version of the one-liner to insert in the previous code to prevent against overwriting 🙂

Great post 🙂

, Mike

Hey There,

That error almost always has to do with unmatched quotation marks. Probably, the easiest way to figure out what’s wrong with it would be to turn your one-liner into a simple script. You’ll get waaaaaay too much information, but the answer will probably be in there.

If not, check test1.txt for any unmatched double quotes, single quotes, backticks, etc and that may lead you to the answer, as well.

Best wishes,

Mike

Thanks a bunch! This saves me a lot of time on a daily basis as I’ve started using this in a script. Just thought I’d come let you know it helped. Although you need to add “quotes” around your find target for this to work properly.

I love perl, but for these use-cases sed would have been more than sufficient?

sed -i ‘s/oldstring/newstring/g’ *

Same w/ the other examples …

Cheers,
Andrej

echoing what everyone said above, but adding the -f switch for find will smooth things out if you happened to have a dir name which ended in dot html:
perl -p -i -e ‘s/oldstring/newstring/g’ `find ./ -type f -name “*.html” `

GaryB:s way is the old school way and in my opinion the best way to do it. Just a minor improvement to include just the files named *.html:

find ./ -type f -name ‘*.html’ -exec perl -i -pe ‘s/oldstring/newstring/g’ {} ;

find . -name someFile.txt -exec perl -p -i -e ‘s/oldString/newString/g’ {} ;

The above command will search recursively for a file named `somFile.txt` and it will perform the string replace.

Building off of Nic’s and others’ posts, this works for file names including spaces and doesn’t update files that don’t need updating:
find . -type f -name ‘*.html’ -print0 | xargs -0 grep -lZ ‘oldstring’ | xargs -0 perl -pi -e ‘s/oldstring/newstring/g’