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Commands using grep from sorted by
Terminal - Commands using grep - 1,637 results
mate - `find * -type f -regex 'REGEX_A' | grep -v -E 'REGEX_B'`
2009-08-12 22:24:08
User: irae
Functions: grep

This does the following:

1 - Search recursively for files whose names match REGEX_A

2 - From this list exclude files whose names match REGEX_B

3 - Open this as a group in textmate (in the sidebar)

And now you can use Command+Shift+F to use textmate own find and replace on this particular group of files.

For advanced regex in the first expression you can use -regextype posix-egrep like this:

mate - `find * -type f -regextype posix-egrep -regex 'REGEX_A' | grep -v -E 'REGEX_B'`

Warning: this is not ment to open files or folders with space os special characters in the filename. If anyone knows a solution to that, tell me so I can fix the line.

find . -name "*.[ch]" | xargs grep "TODO"
dmidecode 2.9 | grep "Maximum Capacity"; dmidecode -t 17 | grep Size
whois domainnametocheck.com | grep match
2009-08-11 13:33:25
User: Timothee
Functions: grep whois
Tags: whois

Returns nothing if the domain exists and 'No match for domain.com' otherwise.

find . -name \*.pdf -exec pdfinfo {} \; | grep Pages | sed -e "s/Pages:\s*//g" | awk '{ sum += $1;} END { print sum; }'
ls -1 *.jpg | while read fn; do export pa=`exiv2 "$fn" | grep timestamp | awk '{ print $4 " " $5 ".jpg"}' | tr ":" "-"`; mv "$fn" "$pa"; done
2009-08-10 00:52:22
User: axanc
Functions: awk export grep ls mv read tr

Renames all the jpg files as their timestamps with ".jpg" extension.

grep . filename
2009-08-09 05:33:58
Functions: grep
Tags: Linux grep

Remove newlines from output.

One character shorter than awk /./ filename and doesn't use a superfluous cat.

To be fair though, I'm pretty sure fraktil was thinking being able to nuke newlines from any command is much more useful than just from one file.

cat filename | grep .
2009-08-09 01:00:59
User: fraktil
Functions: cat grep
Tags: cat Linux grep

Pipe any output to "grep ." and blank lines will not be printed.

ips(){ for if in ${1:-$(ip link list|grep '^.: '|cut -d\ -f2|cut -d: -f1)};do cur=$(ifconfig $if|grep "inet addr"|sed 's/.*inet addr:\([0-9\.]*\).*/\1/g');printf '%-5s%-15s%-15s\n' $if $cur $(nc -s $cur sine.cluenet.org 128 2>/dev/null||echo $cur);done;}
2009-08-07 10:04:46
User: frozenfire
Functions: cut echo grep ifconfig link sed

Gets the internal and external IP addresses of all your interfaces, or the ones given as arguments

ifconfig $devices | grep "inet addr" | sed 's/.*inet addr:\([0-9\.]*\).*/\1/g'
html2text http://checkip.dyndns.org | grep -i 'Current IP Address:'|cut -d' ' -f4
2009-08-06 11:30:32
User: adonis28850
Functions: cut grep

The same as the other user, but smarter, using -d and -f

html2text http://checkip.dyndns.org | grep -i 'Current IP Address:'|cut -c21-36
find . -type f -print0 | xargs -0 -P 4 -n 40 grep -i foobar
2009-08-05 23:18:44
User: ketil
Functions: find grep xargs

xargs -P N spawns up to N worker processes. -n 40 means each grep command gets up to 40 file names each on the command line.

grep -Eho '<[a-ZA-Z_][a-zA-Z0-9_-:]*' * | sort -u | cut -c2-
2009-08-05 21:54:29
User: inkel
Functions: cut grep sort
Tags: sort grep cut xml

This one will work a little better, the regular expressions it is not 100% accurate for XML parsing but it will suffice any XML valid document for sure.

grep -r . /sys/class/net/eth0/statistics
2009-08-05 08:20:39
User: olorin
Functions: grep
Tags: Linux

Within /proc and /sys there are a lot of subdirectories, which carry pseudofiles with only one value as content. Instead of cat-ing all single files (which takes quite a time) or do a "cat *" (which makes it hard to find the filename/content relation), just grep recursively for . or use "grep . /blabla/*" (star instead of -r flag).

For better readability you might also want to pipe the output to "column -t -s : ".

ifconfig | grep "0xffffffff" | awk '{ print $2 }' | xargs -n 1 ifconfig em0 delete
2009-08-04 05:18:36
User: vwal
Functions: awk grep ifconfig xargs

The example command deletes all aliases for network interface 'em0' assuming that the aliases have netmask of and the master IP has some other netmask (such as See here -> http://my.galagzee.com/2009/07/22/deleting-all-network-interface-aliases/ for more on the rationale of this command.

curl -s http://isc.sans.org/sources.html|grep "ipinfo.html"|awk -F"ip=" {'print $2'}|awk -F"\"" {'print $1'}|xargs -n1 sudo iptables -A OUTPUT -j DROP -d > 2&>1
wget `lynx -dump http://www.ebow.com/ebowtube.php | grep .flv$ | sed 's/[[:blank:]]\+[[:digit:]]\+\. //g'`
2009-08-02 14:09:53
User: spaceyjase
Functions: grep sed wget

I wanted all the 'hidden' .flv files from the http link in the command line; wget seemed appropriate, fed with output from lynx, grep the flv files and the normalised via sed (to remove the numeric bullet). Similar to the 'Grab mp3 files' fu. Replace link with your own, grep arg with something more interesting ;) See here for something along the same lines...


Hope you find it useful! Improvements welcome, naturally.

net=DTAG-DIAL ; for (( i=1; i<30; i++ )); do whois -h whois.ripe.net $net$i | grep '^inetnum:' | sed "s;^.*:;$net$i;" ; done
2009-08-01 05:28:19
User: drizzt
Functions: grep sed whois

Useful if you f.i. want to block/allow all connections from a certain provider which uses successive netnames for his ip blocks. In this example I used the german Deutsche Telekom which has DTAG-DIAL followed by a number as netname for the dial in pools.

There are - as always ;) - different ways to do this. If you have seq available you can use

net=DTAG-DIAL ; for i in `seq 1 30`; do whois -h whois.ripe.net $net$i | grep '^inetnum:' | sed "s;^.*:;$net$i;" ; done

or without seq you can use bash brace expansion

net=DTAG-DIAL ; for i in {1..30}; do whois -h whois.ripe.net $net$i | grep '^inetnum:' | sed "s;^.*:;$net$i;" ; done

or if you like while better than for use something like

net=DTAG-DIAL ; i=1 ; while true ; do whois -h whois.ripe.net $net$i | grep '^inetnum:' | sed "s;^.*:;$net$i;" ; test $i = 30 && break ; i=$(expr $i + 1) ; done

and so on.

netstat -ant | grep :80 | grep ESTABLISHED | awk '{print $5}' | awk -F: '{print $1}' | sort | uniq -c | sort -n
grep -E ":(`cat bnd-ips.txt | sed 's/\./\\./g' | tr '\n' '|'`)" access.log
2009-07-30 12:54:55
User: Cowboy
Functions: grep

bnd-ips.txt is a list of IP adresses that is concenated for use as regular expression. Yes, this is still very speedy ;=)

cat /proc/net/ip_conntrack | grep ESTABLISHED | grep -c -v ^#
dpkg --get-selections | grep -v deinstall | cut -f 1
2009-07-29 14:37:36
User: odoepner
Functions: cut grep

Should work on all systems that use dpkg and APT package management.

ipconfig getpacket en0 | grep yi| sed s."yiaddr = "."en0: ". ipconfig getpacket en1 | grep yi| sed s."yiaddr = "."en1: ".
find . -iname '*filename*.doc' | { while read line; do antiword "$line"; done; } | grep -C4 search_term;
2009-07-28 15:49:58
User: Ben
Functions: find grep read

Find Word docs by filename in the current directory, convert each of them to plain text using antiword (taking care of spaces in filenames), then grep for a search term in the particular file.

(Of course, it's better to save your data as plain text to make for easier grepping, but that's not always possible.)

Requires antiword. Or you can modify it to use catdoc instead.