Commands by udog (5)

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

Detect encoding of a text file
This command gives you the charset of a text file, which would be handy if you have no idea of the encoding.

Show all current listening programs by port and pid with SS instead of netstat

Get a free shell account on a community server
Bash process substitution which curls the website 'hashbang.sh' and executes the shell script embedded in the page. This is obviously not the most secure way to run something like this, and we will scold you if you try. The smarter way would be: Download locally over SSL > curl https://hashbang.sh >> hashbang.sh Verify integrty with GPG (If available) > gpg --recv-keys 0xD2C4C74D8FAA96F5 > gpg --verify hashbang.sh Inspect source code > less hashbang.sh Run > chmod +x hashbang.sh > ./hashbang.sh

Rename files in batch

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

Burn CD/DVD from an iso, eject disc when finished.
cdrecord -scanbus will tell you the (x,y,z) value of your cdr (for example, mine is 3,0,0)

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.

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)

Filter IPs out of files

Calculate days on which Friday the 13th occurs (inspired from the work of the user justsomeguy)
Friday is the 5th day of the week, monday is the 1st. Output may be affected by locale.


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: