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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 are 5 alternatives - 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 220 weeks and 2 days ago

ups mangeled comment - here it is again:

while true ; do nc -l 8888 <<<works ; done
Comment by bashrc 220 weeks and 2 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 219 weeks and 4 days 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 219 weeks and 3 days 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 106 weeks ago

Your point of view

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