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Commands using grep from sorted by
Terminal - Commands using grep - 1,520 results
grep -iR find_me ./
2009-02-18 15:38:59
User: lfamorim
Functions: grep
-4

Searching for a String in Multiple Files With Grep

sudo dmidecode | grep Serial\ Number | head -n1
2009-02-18 14:54:28
User: nlinux
Functions: grep head sudo
14

This will give you the Dell Service tag number associated with your machine. Incredibly useful when you need that number for tech support or downloads.

find . | grep deleteme | while read line; do rm $line; done
2009-02-18 00:55:57
User: tec
Functions: find grep read rm
-3

This command deletes all files in all subfolders if their name or path contains "deleteme".

To dry-run the command without actually deleting files run:

find . | grep deleteme | while read line; do echo rm $line; done
ps -ef | grep $USERNAME | awk {'print $2'} | xargs kill [-9]
2009-02-17 20:35:35
User: TheNomad
Functions: awk grep kill ps xargs
3

This is a 'killall' command equivalent where it is not available.

Prior to executing it, set the environment variable USERNAME to the username, whose processes you want to kill or replace the username with the $USERNAME on the command above.

Side effect: If any processes from other users, are running with a parameter of $USERNAME, they will be killed as well (assuming you are running this as root user)

[-9] in square brackets at the end of the command is optional and strongly suggested to be your last resort. I do not like to use it as the killed process leaves a lot of mess behind.

find apps/ -name "*.svn-base" -prune -o -print -name "*.php" | xargs grep -E 'new .+Form\('
2009-02-17 14:56:01
User: ubermuda
Functions: find grep xargs
-1

finds all forms instanciated into a symfony project, pruning svn files.

ls -1 /bin | xargs -l1 whatis 2>/dev/null | grep -v "nothing appropriate"
2009-02-17 14:46:01
User: stinger
Functions: grep ls whatis xargs
4

Get simple description on each file from /bin dir, in list form, usefull for newbies.

grep -c -e '^cpu[0-9]\+' /proc/stat
find /directory/to/search/ -type f -print0 | xargs -0 grep "findtext"
2009-02-17 07:16:32
User: dingobytes
Functions: find grep xargs
2

this will find text in the directory you specify and give you line where it appears.

grep "processor" /proc/cpuinfo | wc -l
2009-02-17 05:39:49
User: jbcurtis
Functions: grep wc
4

/proc/cpuinfo contains information about the CPU.

Search for "processor" in the /proc/cpuinfo file

wc -l, counts the number of lines.

grep -sq "" /etc/lsb-release && lsb_release -rd
2009-02-17 05:21:20
User: int19h
Functions: grep
-3

grep -sq "" filename && command

grep can be used in combination with && to run a command if a file exists.

ps aux | grep "[s]ome_text"
2009-02-17 02:10:50
User: SiegeX
Functions: grep ps
11

The trick here is to use the brackets [ ] around any one of the characters of the grep string. This uses the fact that [?] is a character class of one letter and will be removed when parsed by the shell. This is useful when you want to parse the output of grep or use the return value in an if-statement without having its own process causing it to erroneously return TRUE.

grep -v "^\($\|#\)" <filenames>
2009-02-16 21:40:09
User: raphink
Functions: grep
2

Filter comments and empty lines in files. I find this very useful when trying to find what values are actually set in a very long example config file.

I often set an alias for it, like :

alias nocomment='grep -v "^\($\|#\)"'

cd /usr/ports; grep -F "`for o in \`pkg_info -qao\` ; \ do echo "|/usr/ports/${o}|" ; done`" `make -V INDEXFILE` | \ grep -i \|ports@freebsd.org\| | cut -f 2 -d \|
2009-02-16 21:07:35
User: grep
Functions: cd cut grep
-1

only works for freeBSD where ports are installed in /usr/ports

credit to http://wiki.freebsd.org/PortsTasks

newhostname=$(hostname | awk -F. '{print $1 "." $2}'); ipaddress=$(nslookup `hostname` | grep -i address | awk -F" " '{print $2}' | awk -F. '{print $3 "." $4}' | grep -v 64.142);PS1="[`id -un`.$newhostname.$ipaddress]"' (${PWD}): '; export PS1
2009-02-16 20:11:53
User: simardd
-4

changes the PS1 to something better than default.

[username.hostname.last-2-digits-of-ip] (current directory)

df / | awk '{print $1}' | grep dev | xargs tune2fs -l | grep create
2009-02-16 18:45:03
User: Kaio
Functions: awk df grep tune2fs xargs
9

Very useful set of commands to know when your file system was created.

find . -name "*.jar" | xargs -tn1 jar tvf | grep --color "SearchTerm"
2009-02-16 17:18:36
Functions: find grep xargs
3

Great for finding which jar some pesky class is hiding in!

for I in `echo "show databases;" | mysql | grep -v Database`; do mysqldump $I > "$I.sql"; done
2009-02-16 16:41:05
User: ruedu
Functions: grep
9

Backups all MySQL databases to individual files. Can be put into a script that grabs current date so you have per day backups.

ip route | grep default | awk '{print $3}'
2009-02-16 16:29:03
User: ruedu
Functions: awk grep route
1

This gets you your default route programatically, useful for scripts

LC_ALL=C svn info | grep Revision | awk '{print $2}'
2009-02-16 14:53:52
Functions: awk grep info
-2

This is the simple revision number on stdout, that can be fed to any useful/fun script of yours. Setting LC_ALL is useful if you use another locale, in which case "Revision" is translated and cannot be found. I use this with doxygen to insert my source files revisions into the doc. An example in Doxyfile:

FILE_VERSION_FILTER = "function svn_filter { LC_ALL=C svn info $1 | grep Revision | awk '{print $2}'; }; svn_filter"

Share your ideas about what to do with the revision number !

iptables -L -n --line-numbers | grep xx.xx.xx.xx
2009-02-16 13:38:05
User: nullrouter
Functions: grep iptables
1

This is just one method of checking to see if an IP is blocked via IP tables or CSF. Simple and to the point. Replace xx.xx.xx.xx with the IP you wish to check.

for i in $(svn st | grep "?" | awk '{print $2}'); do svn add $i; done;
find . -type f -name '*.html' -exec grep -H HACKED {} \; > hacklog.txt
2009-02-16 08:57:25
User: nullrouter
Functions: find grep
0

This will check all .HTML file contents for the word "Hacked" and dump it to hacklog.txt. This is great for located all those files affected by nasty Joomla exploits. Change the .HTML to any other extension you wish to check, and of course the word "HACKED" for other searches.

netstat -anl | grep :80 | awk '{print $5}' | cut -d ":" -f 1 | uniq -c | sort -n | grep -c IPHERE
2009-02-16 08:54:08
User: nullrouter
Functions: awk cut grep netstat sort uniq
3

This will tell you who has the most Apache connections by IP (replace IPHERE with the actual IP you wish to check). Or if you wish, remove | grep -c IPHERE for the full list.

netstat -pant 2> /dev/null | grep SYN_ | awk '{print $5;}' | cut -d: -f1 | sort | uniq -c | sort -n | tail -20
2009-02-16 08:49:38
3

List top 20 IP from which TCP connection is in SYN_RECV state.

Useful on web servers to detect a syn flood attack.

Replace SYN_ with ESTA to find established connections

find . -type f -exec grep -l pattern {} \; | xargs vi +/pattern