How can I grep while avoiding 'Too many arguments' [duplicate]

Question

I was trying to clean out some spam email and ran into an issue. The amount of files in queue, were so large that my usual command was unable to process. It would give me an error about too many arguments.

I usually do this

grep -i [email protected] 1US* | awk -F: '{print $1}' | xargs rm

1US* can be anything between 1US[a-zA-Z]. The only thing I could make work was running this horrible contraption. Its one file, with 1USa, 1USA, 1USb etc, through the entire alphabet. I know their has to be a way to run this more efficiently.

grep -s $SPAMMER /var/mailcleaner/spool/exim_stage1/input/1USa* | awk -F: '{print $1}' | xargs rm
grep -s $SPAMMER /var/mailcleaner/spool/exim_stage1/input/1USA* | awk -F: '{print $1}' | xargs rm

Answer 1

Run several instances of grep. Instead of

grep -i [email protected] 1US* | awk '{...}' | xargs rm

do

(for i in 1US*; do grep -li user@domain "$i"; done) | xargs rm

Note the -l flag, since we only want the file name of the match. This will both speed up grep (terminate on first match) and makes your awk script unrequired. This could be improved by checking the return status of grep and calling rm, not using xargs (xargs is very fragile, IMO). I'll give you the better version if you ask.

Hope it helps.

Answer 2

you can use find to find all files which name's starting with the pattern '1US'. Then you can pipe the output to xargs which will take care, that the argument list will not growing to much and handle the grep call. Note that I've used a nullbyte to separate filenames for xargs. This avoids problems with problematic file names. ;)

find -maxdepth 1 -name '1US*' -printf '%f\0' | xargs -0 grep -u user@domain | awk ...

Answer 3

The -exec argument to find is useful here, I've used this myself in similar situations.

E.g.

# List the files that match
find /path/to/input/ -type f -exec grep -qiF [email protected] \{\} \; -print
# Once you're sure you've got it right
find /path/to/input/ -type f -exec grep -qiF [email protected] \{\} \; -delete