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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.

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One command line web server on port 80 using nc (netcat)

Terminal - One command line web server on port 80 using nc (netcat)
while true ; do nc -l 80 < index.html ; done
2011-08-31 15:17:33
User: ztank1013
Functions: true
One command line web server on port 80 using nc (netcat)

Very simple web server listening on port 80 will serve index.html file or whatever file you like pointing your browser at http://your-IP-address/index.html for example.

If your web server is down for maintenance and you'd like to inform your visitors about it, quickly and easily, you just have to put into the index.html file the right HTML code and you are done! Of course you need to be root to run the command using port 80.


There is 1 alternative - vote for the best!

Terminal - Alternatives
nc -kl 5432 -c 'echo -e "HTTP/1.1 200 OK\r\n$(date)\r\n\r\n";echo "<p>How are you today?</p>"'
2013-11-12 14:00:11
User: gvitalie
Functions: echo

-k, --keep-open will keep connection alive, and we could exclude using 'while true'

nc is such a powerful command, it could be used instead of any OS! :p

Know a better way?

If you can do better, submit your command here.

What others think

cool - or deliver contents directly from a string:

while true ; do nc -l 8888

Comment by bashrc 188 weeks and 6 days ago

ups mangeled comment - here it is again:

while true ; do nc -l 8888 <<<works ; done
Comment by bashrc 188 weeks and 6 days ago

Don't you need to prepend proper HTTP headers to the output?

Firefox, lynx and Chromium allow it to pass, but Midori/Webkit gives the bad-response-from-server error I expected. Does the HTTP spec allow for a zero-length header to the response message?

Comment by Mozai 188 weeks ago

@Mozai Yes you are totally right! HTTP/1.1 version requires at least the status line in the response:

Status-Line = HTTP-Version SP Status-Code SP Reason-Phrase CRLF

hence there are a couple of way to fix the command:

[1] put this at the beginning of the index.html file:

HTTP/1.1 200 OK (followed by a CRLF carriage return and a line feed

[2] or you may want to fine tune the initial command to look like this:

while true; do { echo -e 'HTTP/1.1 200 OK\r\n'; cat index.html; } | nc -l 80; done

Not sure but additional '\r\n' might be necessary...

Comment by ztank1013 188 weeks ago

you could avoid using 'while true' with -k, --keep-open nc option:

nc -kl 5432 -c 'echo -e "HTTP/1.1 200 OK\r\n$(date)\r\n\r\n";echo "How are you today?"'

Comment by gvitalie 74 weeks and 4 days ago

Your point of view

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