What's this?

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/

Get involved!

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.

Universal configuration monitoring and system of record for IT.

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:



2011-03-12 - Confoo 2011 presentation
Slides are available from the commandlinefu presentation at Confoo 2011: http://presentations.codeinthehole.com/confoo2011/
2011-01-04 - Moderation now required for new commands
To try and put and end to the spamming, new commands require moderation before they will appear on the site.
2010-12-27 - Apologies for not banning the trolls sooner
Have been away from the interwebs over Christmas. Will be more vigilant henceforth.
2010-09-24 - OAuth and pagination problems fixed
Apologies for the delay in getting Twitter's OAuth supported. Annoying pagination gremlin also fixed.

Top Tags



Download file with multiple simultaneous connections

Terminal - Download file with multiple simultaneous connections
aria2c -s 4 http://my/url
2009-08-11 22:34:00
User: jrk
Download file with multiple simultaneous connections

`aria2c` (from the aria2 project) allows. Change -s 4 to an arbitrary number of segments to control the number of concurrent connections. It is also possible to provide multiple URLs to the same content (potentially over multiple protocols) to download the file concurrently from multiple hosts.


There are 2 alternatives - vote for the best!

Terminal - Alternatives
aria2c -x 4 http://my/url
2014-07-26 03:06:33
User: lx45803

jrk's aria2 example is incorrect. -s specifies the global connection limit; the per-host connection limit is specified with -x.

Know a better way?

If you can do better, submit your command here.

What others think

isn't this considered rather bad netiquette?

Comment by thebillywayne 297 weeks and 4 days ago

You may encounter the certificate verification error with HTTPS server.

Comment by hemanth 297 weeks and 4 days ago

It was just as bad when "puf" did it, 5+ years ago :-)

Comment by eichin 297 weeks and 3 days ago

firefox extension downthemall does this - why is it considered bad?

Comment by stuntkiwi 242 weeks and 4 days ago

It is recommended to keep number of simultaneous connections to a maximum of 2 per host, as per RFC2616. As to why more is bad: you might hose the available resources of the host, and this could be bad for high-traffic hosts. Some programs like DownThemAll have default settings that take this for granted. I always set the number of simultaneous connections to 1 per host when installing DownThemAll.

Apart from above sideline notes, this command is how you download with simultaneous connections. If you want to spread across mirrors, just add the mirror URLs. E.g.:

aria2c -s 4 http://my/url http://my_mirror1/url http://my_mirror2/url ...
Comment by syockit 202 weeks and 6 days ago

Your point of view

You must be signed in to comment.