I have a big apache log file and I need to filter that and leave only (in a new file) the log from a certain IP: 192.168.1.102
I try using this command:
sed -e "/^192.168.1.102/d" < input.txt > output.txt
But "/d" removes those entries, and I needt to leave them.
Thanks.
What about using grep?
cat input.txt | grep -e "^192.168.1.102" > output.txt
EDIT: As noted in the comments below, escaping the dots in the regex is necessary to make it correct. Escaping in the regex is done with backslashes:
cat input.txt | grep -e "^192\.168\.1\.102" > output.txt
cat, it just slows things down, and "." should be escaped: grep -e "^192\.168\.1\.102" input.txt > output.txt
192_168_1_102 as well, without escaping.
grep -F '192.168.1.102' which sees the dots as literal, but you can't anchor it to the beginning of the line this way.sed -n 's/^192\.168\.1\.102/&/p'
sed is faster than grep on my machines
sed takes 1.676s and grep takes 4.633ssed -n /^192\.168\.1\.102/p' input.txt. The speed depends on the pattern. By varying the pattern, I got some results that were faster for sed and some for grep.I think using grep is the best solution but if you want to use sed you can do it like this:
sed -e '/^192\.168\.1\.102/b' -e 'd'
The b command will skip all following commands if the regex matches and the d command will thus delete the lines for which the regex did not match.
.) has meaning in a regular expression so you need to escape it if you want a literal dot.