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

Test your total disk IO capacity, regardless of caching, to find out how fast the TRUE speed of your disks are
Depending on the speed of you system, amount of RAM, and amount of free disk space, you can find out practically how fast your disks really are. When it completes, take the number of MB copied, and divide by the line showing the "real" number of seconds. In the sample output, the cached value shows a write speed of 178MB/s, which is unrealistic, while the calculated value using the output and the number of seconds shows it to be more like 35MB/s, which is feasible.

Remove today's installed packages

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

a function to find the fastest DNS server
http://public-dns.info gives a list of online dns servers. you need to change the country in url (br in this url) with your country code. this command need some time to ping all IP in list.

Convert tab separate file (TSV) to JSON with jq
With this command you can convert a tab separate file (TSV) into a JSON file with jq. For example, this input.tsv i-0b9adca882e5e6326 172.16.0.188 i-088dd69e5c3624888 172.16.0.102 i-0e70eac180537d4aa 172.16.0.85 will produce the showed output.

find duplicate messages in a Maildir
# find assumes email files start with a number 1-9 # sed joins the lines starting with " " to the previous line # gawk print the received and from lines # sort according to the second field (received+from) # uniq print the duplicated filename # a message is viewed as duplicate if it is received at the same time as another message, and from the same person. The command was intended to be run under cron. If run in a terminal, mutt can be used: mutt -e "push otD~=xq" -f $folder

Generate 10 pronunciable passwords
A great password generation tool. http://www.adel.nursat.kz/apg/

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Check if system is 32bit or 64bit

Creating shortened URLs from the command line


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: