Commands by karld

Commands by karld (3)

sorted by

Avoid using seq and pad numbers with leading zeros

zsh only I always hated resorting to using $(seq -w 1 99) to pad numbers. zsh provides a shortcut that couldn't be more intuitive. It also works in reverse {99..01} Show Sample Output
This is sample output - yours may be different.
```
001
002
...
998
999
```
-1

for i in {001..999}; print $i

karld · 2009-02-16 23:03:53 7
Always tail/edit/grep the latest file in a directory of timestamped files

zsh only If you have this command in your history, you can always re-run it and have it reference the latest file. The glob matches all timestamped files and then the resulting array is sorted by modification time (m) and then the first element in the sorted array is chosen (the latest)
This is sample output - yours may be different.
5

tail -f /path/to/timestamped/files/file-*(om[1])

karld · 2009-02-16 22:55:16 8
send substituted text to a command without echo, pipe

zsh only - This avoids the need for echo "message" | which creates an entire subshell. Also, the text you are most likely to edit is at the very end of the line, which, in my opinion, makes it slightly easier to edit. Show Sample Output
This is sample output - yours may be different.
```
none
```
1

nc localhost 10000 <<< "message"

karld · 2009-02-16 22:14:28 7

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

find out how many days since given date

You can also do this for seconds, minutes, hours, etc... Can't use dates before the epoch, though.

Delete empty directories

Recursively delete empty directories. Use with care.

get a random command

This command will show an random command. this is useful if you want to explore various random commands.

ping with timestamp

Delete empty directories recursively

Sort specific lines while editing within vi

Sort lines within vi editor. In this example sort lines 33-61 and lines 4-9 asciibetically.

php show list pdo module

can show module other

Printable random characters

Reads psuedorandom bytes from /dev/urandom, filtering out non-printable ones. Other character classes can be used, such as [:alpha:], [:digit:] and [:alnum:]. To get a string of 10 lowercase letters: $ tr -dc '[:lower:]' < /dev/urandom | head -c 10

Count the number of characters in each line

Search some text from all files inside a directory

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 by karld