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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
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Commands using grep from sorted by
Terminal - Commands using grep - 1,661 results
netstat -anp --tcp --udp | grep LISTEN
sqlite3 mydb.sqlite3 '.dump' | grep -vE '^(BEGIN|COMMIT|CREATE|DELETE)|"sqlite_sequence"' | sed -r 's/"([^"]+)"/`\1`/' | tee mydb.sql | mysql -p mydb
2009-10-02 14:40:51
User: mislav
Functions: grep sed tee
Tags: mysql sqlite dump

Filters out all non-insert SQL operations (we couldn't filter out only lines starting with "INSERT" because inserts can span multiple lines), quotes table names with backticks, saves dump to a file and pipes it straight to mysql.

This transfers only data--it expects your schema is already in place. In Ruby on Rails, you can easily recreate the schema in MySQL with "rake db:schema:load RAILS_ENV=production".

md5sum --check MD5SUMS | grep -v ": OK"
2009-10-02 05:21:17
User: gpenguin
Functions: grep md5sum

All valid files are withheld so only failures show up. No output, all checks good.

sh -c 'S=askapache R=htaccess; find . -mount -type f|xargs -P5 -iFF grep -l -m1 "$S" FF|xargs -P5 -iFF sed -i -e "s%${S}%${R}%g" FF'

I needed a way to search all files in a web directory that contained a certain string, and replace that string with another string. In the example, I am searching for "askapache" and replacing that string with "htaccess". I wanted this to happen as a cron job, and it was important that this happened as fast as possible while at the same time not hogging the CPU since the machine is a server.

So this script uses the nice command to run the sh shell with the command, which makes the whole thing run with priority 19, meaning it won't hog CPU processing. And the -P5 option to the xargs command means it will run 5 separate grep and sed processes simultaneously, so this is much much faster than running a single grep or sed. You may want to do -P0 which is unlimited if you aren't worried about too many processes or if you don't have to deal with process killers in the bg.

Also, the -m1 command to grep means stop grepping this file for matches after the first match, which also saves time.

expdp user/password FLASHBACK_SCN=$(echo -e "select current_scn from v\$database;" | sqlplus / as sysdba 2>/dev/null| grep [0-9][0-9][0-9][0-9][0-9][0-9]*)
2009-10-01 08:55:20
User: peshay
Functions: as echo grep

Creates a consistent datapumpt export on an Oracle database with the current sequence number, while the system is running and changes happens on the database.

check_dns_no() { for i in $* ; do if `wget -O - -q http://www.norid.no/domenenavnbaser/whois/?query=$i.no | grep "no match" &>/dev/null` ; then echo $i.no "available" ; fi ; sleep 1 ;done }
2009-09-30 21:17:33
User: xeor
Functions: echo grep sleep
Tags: wget dig dns

Mostly for Norwegians, but easily adoptable to others. Very handy if you are brainstorming for a new domainname.

Will only display the available ones..

You can usually do this better with dig, but if you dont have dig, or the TLD only have an online service to check with, this will be usefull..

strings /boot/kernel-file | grep 2.6
2009-09-30 06:21:40
Functions: grep strings

recently some in the #linux shared this. to find out the kernel version name from the binary without using uname

while true; do curl -s http://www.commandlinefu.com/commands/view/3643/log-a-commands-votes | grep 'id="num-votes-' | sed 's;.*id="num-votes-[0-9]*">\([0-9\-]*\)</div>;\1;' >> votes; sleep 10; done
2009-09-26 00:55:24
User: matthewbauer
Functions: grep sleep

Log a command's votes,

then run:

gnuplot -persist <(echo "plot 'votes' with lines")
grep . filename > newfilename
wget -q -O - 'http://wap.weather.gov.hk/' | sed -r 's/<[^>]+>//g;/^UV/q' | grep -v '^$'
grep -v "^$" filename > newfilename
2009-09-24 12:21:43
User: eastwind
Functions: grep

The ^$ within the quotes is a regular expression: ^=beginning of line, $=end of line, with no characters between.

sudo lshw -C cpu|grep width
mplayer -vo dummy -ao dummy -identify * 2>&1 | grep ID_LENGTH | sed 's/.*=\([0-9]*\)/\1/' | xargs echo | sed 's/ /+/g' | bc | awk 'S=$1; {printf "%dh:%dm:%ds\n",S/(60*60),S%(60*60)/60,S%60}'
2009-09-24 10:33:19
User: Strawp
Functions: awk bc echo grep sed xargs

You're behind on your TV catch-up, but how far behind? This command tries to open mplayer against all files in the current dir. If it's a video file it will contain ID_LENGTH, which is summed and output in hours, minutes and seconds.

Someone better at awk could probably reduce this down a lot.

grep CONFIG $(which mysqlbug)
grep -RnisI <pattern> *
2009-09-22 15:09:43
User: birnam
Functions: grep
Tags: bash grep

This is how I typically grep. -R recurse into subdirectories, -n show line numbers of matches, -i ignore case, -s suppress "doesn't exist" and "can't read" messages, -I ignore binary files (technically, process them as having no matches, important for showing inverted results with -v)

I have grep aliased to "grep --color=auto" as well, but that's a matter of formatting not function.

grep -r <pattern> * .[!.]*
find . -type f -exec grep -i <pattern> \;
find . -type f -print0 | xargs -0 grep -i <pattern>
netstat -an | grep -Ec '^tcp.+ESTABLISHED$'
find . | xargs file | grep ".*: .* text" | sed "s;\(.*\): .* text.*;\1;"
xev -id `xwininfo | grep 'Window id' | awk '{print $4}'`
2009-09-19 22:47:16
User: ktoso
Functions: awk grep

After executing this, click on a window you want to track X Window events in.

Explaination: "xev will track events in the window with the following -id, which we get by greping window information obtained by xwininfo"

netstat -lantp | grep -i stab | awk -F/ '{print $2}' | sort | uniq
2009-09-19 14:54:31
User: ProMole
Functions: awk grep netstat sort

Show apps that use internet connection at the moment.

Can be used to discover what programms create internet traffic. Skip the part after awk to get more details, though it will not work showing only unique processes.

This version will work with other languages such as Spanish and Portuguese, if the word for "ESTABLISHED" still contain the fragment "STAB"(e.g. "ESTABELECIDO")

netstat -lantp | grep -i establ | awk -F/ '{print $2}' | sort | uniq
netstat -lantp | grep -i establ | awk -F/ '{print $2}' | uniq | sort
2009-09-19 13:54:36
User: ktoso
Functions: awk grep netstat uniq

Can be used to discover what programms create internet traffic. Skip the part after awk to get more details.

Has anyone an idea why the uniq doesn't work propperly here (see sample output)?

echo "Decode this"| tr [a-zA-Z] $(echo {a..z} {A..Z}|grep -o .|sort -R|tr -d "\n ")