Commands tagged regexp sorted by votes

Commands tagged regexp (6)

sorted by

Are there any words in the English language that use at least half of the alphabet without repeating any letters?

This is the most straightforward approach: first regexp limits dictionary file to words with thirteen or more characters, second regexp discards any words that have a letter repeated. (Bonus challenge: Try doing it in a single regexp!) Show Sample Output
This is sample output - yours may be different.
```
# You'll just have to try it to find out!
```
6

cat /usr/share/dict/words | egrep '^\w{13,}$' | egrep -iv '(\w).*\1'

hackerb9 · 2014-09-29 12:52:09 16
Parse YouTube url (get youtube video id)

url can be like any one of followings: url="MejbOFk7H6c" url="http://youtu.be/MejbOFk7H6c" url="https://youtube.com/watch?feature=player_embedded&v=MejbOFk7H6c#t" url="//www.youtube.com/v/MejbOFk7H6c?hl=ru_RU&version=3&rel=0" url="http://www.youtube.com/embed/MejbOFk7H6c?feature=player_embedded" If url mismatching, whole url will be returned. Show Sample Output
This is sample output - yours may be different.
```
MejbOFk7H6c
```
3

sh -c 'url="http://youtu.be/MejbOFk7H6c"; vid="`for i in ".*youtu\.be/$[^\/&?#]\+$" ".*youtu.\+v[=/]$[^\/&?#]\+$" ".*youtu.\+embed/$[^\/&?#]\+$"; do expr "${url}" : "${i}"; done`"; if [ -n "${vid}" ]; then echo ${vid}; else echo "${url}"; fi'

qwertyroot · 2013-09-04 19:33:09 9
get rid of lines with non ascii characters

found here: https://stackoverflow.com/a/9035939
This is sample output - yours may be different.
1

grep -v $'[^\t\r -~]' my-file-with-non-ascii-characters

saps · 2019-03-13 14:46:02 34
extract email addresses from some file (or any other pattern)
This is sample output - yours may be different.
1

grep -Eio '([[:alnum:]_.-]{1,64}@[[:alnum:]_.-]{1,252}?\.[[:alpha:].]{2,6})'

mikhail · 2020-07-22 22:40:33 170
Get user's full name in Mac OS X

Its possible to user a simple regex to extract de username from the finger command. The final echo its optional, just for remove the initial space Show Sample Output
This is sample output - yours may be different.
```
$ finger $(whoami) | egrep -o 'Name: [a-zA-Z0-9 ]{1,}' | cut -d ':' -f 2 | xargs echo                                                           2.1.2
Sebastian Webber
```
0

finger $(whoami) | egrep -o 'Name: [a-zA-Z0-9 ]{1,}' | cut -d ':' -f 2 | xargs echo

swebber · 2014-09-24 01:22:07 9
Get user's full name in Mac OS X
This is sample output - yours may be different.
0

finger $(whoami) | perl -ne '/Name: ([a-zA-Z0-9 ]{1,})/ && print "$1\n"'

zil0g · 2014-09-30 11:37:47 11

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

Merge files, joining each line in one line

Change every instance of OLD to NEW in file FILE

Very quick way to change a word in a file. I use it all the time to change variable names in my PHP scripts (sed -i 's/$oldvar/$newvar/g' index.php)

Check syntax of all Perl modules or scripts underneath the current directory

Finds all *.p[ml]-files and runs a perl -c on them, checking whether Perl thinks they are syntactically correct

Find usb device in realtime

Using this command you can track a moment when usb device was attached.

aptitude easter eggs

this is a reference to Antoine de St. Exupery's "The Little Prince"

Remind yourself to leave in 15 minutes

If you spend most of your time in front of the terminal, leave is a useful reminder. Leave can have absolute form: leave 1555 reminds you to leave at 3:55PM

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.

Creates a symbolic link or overwrites an existing one

-n: dereference the existing link -v: (optional) to be sure of what is being done -f: force the deletion of the existing one -s: creates a symlink Be careful: the destination can also be a file or a directory and it will be overwritten.

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.

Create multiple subfolders in one command.

Instead of typing separate commands to create various subfolders, we can create multiple subfolders by listing them between brackets and separated by commas.

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:

» all commands
» commands with 3 up-votes (commandlinefu3)
» commands with 10 up-votes (commandlinefu10)
» commands tagged regexp

Commands tagged regexp (6) the last day the last week the last month all time sorted by date votes

What's this?

Check These Out

Stay in the loop…

Commands tagged regexp (6)

sorted by