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Terminal - All commands - 11,616 results
^foo^bar
2009-01-26 13:25:37
User: root
451

Really useful for when you have a typo in a previous command. Also, arguments default to empty so if you accidentally run:

echo "no typozs"

you can correct it with

^z
cp file.txt{,.bak}
2009-01-26 12:11:29
User: root
Functions: cp
35

Uses shell expansion to create a back-up called file.txt.bak

grep -o "\(new \(\w\+\)\|\w\+::\)" file.php | sed 's/new \|:://' | sort | uniq -c | sort
2009-01-26 12:08:47
User: root
Functions: grep sed sort uniq
-2

This grabs all lines that make an instantation or static call, then filters out the cruft and displays a summary of each class called and the frequency.

sed '1000000!d;q' < massive-log-file.log
2009-01-26 11:50:00
User: root
Functions: sed
18

Sed stops parsing at the match and so is much more effecient than piping head into tail or similar. Grab a line range using

sed '999995,1000005!d' < my_massive_file
find /path/to/dir -type f -print0 | xargs -0 rm
2009-01-26 11:30:47
User: root
Functions: find xargs
12

Using xargs is better than:

find /path/to/dir -type f -exec rm \-f {} \;

as the -exec switch uses a separate process for each remove. xargs splits the streamed files into more managable subsets so less processes are required.

find . -name "*.php" -exec grep \-H "new filter_" {} \;
2009-01-26 10:43:09
User: root
Functions: find grep
0

This greps all PHP files for a given classname and displays both the file and the usage.

sudo !!
2009-01-26 10:26:48
User: root
1001

Useful when you forget to use sudo for a command. "!!" grabs the last run command.

alias cr='find . 2>/dev/null -regex '\''.*\.\(c\|cpp\|pc\|h\|hpp\|cc\)$'\'' | xargs grep --color=always -ni -C2'
2009-01-26 08:54:25
User: chrisdrew
Functions: alias grep xargs
0

Creates a command alias ('cr' in the above example) that searches the contents of files matching a set of file extensions (C & C++ source-code in the above example) recursively within the current directory. Search configured to be in colour, ignore-case, show line numbers and show 4 lines of context. Put in shell initialisation file of your choice. Trivially easy to use, e.g:

cr sha1_init
du | sort -gr > file_sizes
2009-01-26 01:12:54
User: chrisdrew
Functions: du sort
6

Recursively searches current directory and outputs sorted list of each directory's disk usage to a text file.

watch "df | grep /path/to/drive"
2009-01-25 21:16:41
User: root
4

This can be useful when a large remove operation is taking place.

echo "ls -l" | at midnight
2009-01-25 21:07:42
User: root
Functions: at echo
212

This is an alternative to cron which allows a one-off task to be scheduled for a certain time.

tail -10000 access_log | awk '{print $1}' | sort | uniq -c | sort -n | tail
2009-01-25 21:01:52
User: root
Functions: awk sort tail uniq
20

This uses awk to grab the IP address from each request and then sorts and summarises the top 10.

find . \( -name "*.php" -o -name "*.js" \) -exec svn propset svn:keywords Id {} \;
find . -type f | wc -l
ps aux | sort -nk +4 | tail
2009-01-23 17:12:33
User: root
Functions: ps sort
93

ps returns all running processes which are then sorted by the 4th field in numerical order and the top 10 are sent to STDOUT.

myisamchk /path/to/mysql/files/*.MYI
2009-01-22 10:20:00
User: root
0

See http://dev.mysql.com/doc/refman/5.0/en/myisamchk.html for further details. You can also repair all tables by running:

myisamchk -r *.MYI