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Terminal - All commands - 11,859 results
mysql -u uname dbname -e "show tables" | grep -v Tables_in | grep -v "+" | gawk '{print "drop table " $1 ";"}' | mysql -u uname dbname
echo 2006-10-10 | grep -c '^[0-9][0-9][0-9][0-9]-[0-9][0-9]-[0-9][0-9]$'
2009-05-11 22:18:43
User: rez0r
Functions: echo grep
-1

Quick and easy way of validating a date format of yyyy-mm-dd and returning a boolean, the regex can easily be upgraded to handle "in betweens" for mm dd or to validate other types of strings, ex. ip address.

Boolean output could easily be piped into a condition for a more complete one-liner.

mail -s scream-dump user@example.com < /tmp/scream-dump
geoip() { wget -qO - http://freegeoip.net/xml/$1 | sed '3,12!d;s/<//g;s/>/: /g;s/\/.*//g' ; }
i=10;for o in *.mp3; do i=$(printf "%02d" $i); mv $o $i$o; ((i = $i + 2)); done
2009-04-13 12:33:52
User: bazzawill
Functions: mv printf
-1

This command adds the numbers 10, 12, 14 to a bunch of mp3's in the current working directory. You can then run the command replacing the inital i=10 with i=11 to add 11,13,15 in another directory then mv the files together and the first files interweave with the second group of files. I used this to weave a backlog of a podcast with other podcast so I didn't get sick of one while I was catching up. I started at 10 because printf blows up with 0 padded numbers 08 and 09 which kind of makes the printf command redundant as it was used to pad numbers 1 - 9 so they would come first and not get sorted incorrectly

$foo[(I)$foo[-1]]
2009-10-01 20:07:14
User: andrew112358
-1

Returns the index of the last element in the array.

curl -s http://whatthecommit.com | html2text | sed '$d'
2011-04-14 16:51:53
User: zbeekman
Functions: sed
-1

Requires html2text. Print bad, but often funny commit messages from whatthecommit.com

screen -ls | grep D
2012-03-01 14:05:40
User: peter4512
Functions: grep screen
-1

If you have many screen sessions, it can be difficult to find the id of the one you just detached from so you can re-attach using `screen -x -S `

doloop() { DONT=/tmp/do-run-run-run; while true; do touch $DONT; (sleep 30; rm $DONT;) & $1 ; if [ -e $DONT ]; then echo restarting too fast; return ; fi ; done }
2009-02-21 02:11:18
User: evil_otto
Functions: echo return rm sleep touch
-1

This runs a command continuously, restarting it if it exits. Sort of a poor man's daemontools. Useful for running servers from the command line instead of inittab.

grep -i '<searchTerm>\|<someOtherSearchTerm>' <someFileName>
2009-05-11 23:05:54
User: scifisamurai
Functions: grep
-1

This is a simple but useful command to search for multiple terms in a file at once. This prevents you from having to do mutliple grep's of the same file.

find . -name "*.java" -type f -perm +600 -print | xargs -I _ sh -c 'grep -q hexianmao _ && iconv -f gb2312 -t utf8 -o _ -c _ '
2011-03-08 13:02:25
User: Sunng
Functions: find iconv sh xargs
Tags: find xargs iconv
-1

One of my friends committed his code in the encoding of GB2312, which broke the build job. I have to find his code and convert.

mkdir copy{1,2}; gzip -dc file.tar.gz | tee >( tar x -C copy1/ ) | tar x -C copy2/
2011-04-14 17:02:05
User: depesz
Functions: gzip mkdir tar tee
Tags: bash tee tar
-1

Sometimes you might need to have two copies of data that is in tar. You might unpack, and then copy, but if IO is slow, you might lower it by automatically writing it twice (or more times)

fileName() { echo "$1" | grep -o "[^/]*$"; }
2011-08-19 18:16:22
User: totti
Functions: echo grep
Tags: grep basename
-1
fileName /path/to/file.ext

quivalent to

basename /path/to/file.ext
svn log --stop-on-copy | grep r[0-9] | awk '{print $1}' | sed "s/r//" | sort -n | head -1
git branch -D `git branch | awk '{ if ($0 !~ /next|master/) printf "%s", $0 }'`
2011-04-14 17:43:21
User: denheck
Functions: awk printf
-1

This command will delete all branches in your git repository other than next and master. I use this to cleanup my git repos after making multiple branches and merging them back into next. It's much faster than individually deleting each expired branch using:

git branch -D <branch_name>
df -x tmpfs | grep -vE "(gvfs|procbususb|rootfs)"
2009-02-09 01:54:05
User: bones7456
Functions: df grep
-1

show physical disk using, except tmpfs, gvfs, and so on.

mkdir save && for f in *.mp3; do lame -b xxx "$f" ./save/"${f%.mp3}.mp3"; done
2011-05-30 17:19:36
User: o0110o
Functions: mkdir
-1

Batch Convert MP3 Bitrate to xxxkbps, all the new files will be placed in a folder called "save". Please replace xxx with the desired bitrate. WARNING!!! This will erase any tag information; this is where Picard or EasyTAG will come in handy.

Amharic software
tac $FILETOREVERSE
sleep 15 ; `echo "done" | mail -s "done" 4158575309@txt.att.net`
2012-04-16 01:28:16
User: vajrapani666
Functions: mail sleep
-1

Replace "4158575309@txt.att.net" with your carrier's SMS gateway identifier. The one in the sample is for AT&T. More here https://en.wikipedia.org/wiki/List_of_SMS_gateways. Helpful for getting notifications about long running commands. ";" executes regardless of exit status of last command. && will only notify you if the command succeeds.

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.

top -bn 1 | awk '{if($1 ~ /^[0-9]+$/ && $9 > 97) {print $1;exit}}'|xargs kill
2010-06-02 13:51:40
User: chx
Functions: awk top xargs
-1

I found Flash eating one of my CPUs after resume, the command above will help with that. For optional kicks you can put it into a script in /etc/pm/sleep.d/ (aspect in #swhack wrote this for me)

sudo sh /usr/share/doc/libdvdread4/install-css.sh
dd of=output.txt if=input.txt ibs=1 skip=$(expr `stat -c%s input.txt` / 2)
find . -maxdepth 1 -type d | grep -Pv "^.$" | sort -rn --field-separator="-" | sed -n '3,$p' | xargs rm -rf