commandlinefu.com is the place to record those command-line gems that you return to again and again.
Delete that bloated snippets file you've been using and share your personal repository with the world. 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.
If you have a new feature suggestion or find a bug, please get in touch via http://commandlinefu.uservoice.com/
You can sign-in using OpenID credentials, or register a traditional username and password.
First-time OpenID users will be automatically assigned a username which can be changed after signing in.
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.
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:
With sed you can replace strings on the fly.
Short and concise output appropiate for scripts.
Cleaner with a mailto assignment in crontab (if the command fails you get an email):
10,30,50 * * * * ping -q -c1 -w3 192.168.0.14 >/dev/null
Every 20 minutes test if host with IP 192.168.0.14 is 'dead' or not reachable.
The line should be put in your crontab file.
Every 20 minutes ping host with IP address 192.168.0.14. If it's not 'alive' or not reachable, then display something eye-catching (here xeyes) on the desktop.
Hint for newbies: edit crontab with
has the benefit of being a bit more cross-platform.
Get just the IP address for a given hostname. For best results, make this a function in your shell rc file so that it can be used for things like traceroute:
Titus:~$ traceroute `getip foo.com`
traceroute to 220.127.116.11 (18.104.22.168), 64 hops max, 52 byte packets
This version uses host and no ruby.
Performs a reverse DNS lookup, variants include:
DNS cache snooping