All commands (14,187)

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Share Your Commands


Check These Out

Your name backwards

Partition a sequence of disk drives for LVM with fdisk
So, I'm using a CentOS VM in VirtualBox, and created four new disks in the SCSI controller. The VM created the folders: /dev/sda /dev/sdb /dev/sdc /dev/sdd Using a 'for loop' all disks are partitioned for LVM.

split a file by a specific number of lines
Splits the file "my_file" every 500 lines. Will create files called xx01 xx02 and so on. You can change the prefix by using the -f option. Comes in handy for splitting logfiles for example. I am using it for feeding a logfile parser with smaller files instead of one big file (due to performance reasons)

What is my public IP-address?
alternative to $curl ifconfig.me for those that don't have curl

Use Perl like grep
Much better alternatives - grep-alikes using perl regexps. With more options, and nicer outputs.

grep certain file types recursively
doesn't do case-insensitive filenames like iname but otherwise likely to be faster

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

move you up one directory quickly
In bash, this turns on auto cd. If a command is just a directory name, it cd's into that directory.

Print one . instead of each line
If you're running a command with a lot of output, this serves as a simple progress indicator. This avoids the need to use `/dev/null` for silencing. It works for any command that outputs lines, updates live (`fflush` avoids buffering), and is simple to understand.

Remove a line from a file using sed (useful for updating known SSH server keys when they change)
For example, to remove line 5 from foo, type: vi +5d +wq foo


Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for: