I wanted a one-liner that didn't download any files; here is an example of piping the cookie output into the next request. I only tested the following on Gentoo, but it should work in most *nix environments:

wget -q -O /dev/null --save-cookies /dev/stdout --post-data 'u=user&p=pass' 'http://example.com/login' | wget -q -O - --load-cookies /dev/stdin 'http://example.com/private/page'

(This is one line, though it likely wraps on your browser)

If you want the output saved to a file, change -O - to -O /some/file/name.ext

You don't need cURL to do POSTed form data. --post-data 'key1=value1&key2=value2' works just fine. Note: you can also pass a file name to wget with the POST data in the file.

A solution which uses lynx and wget.

Note: Lynx has to have been compiled with the --enable-persistent-cookies flag for this to work

When you want to use wget to download some file from a site which requires login, you just need a cookie file. In order to generate the cookie file, I choose lynx. lynx is a text web browser. First you need a configure file for lynx to save cookie. Create a file lynx.cfg. Write these configuration into the file.

SET_COOKIES:TRUE
ACCEPT_ALL_COOKIES:TRUE
PERSISTENT_COOKIES:TRUE
COOKIE_FILE:cookie.file

Then start lynx with this command:

lynx -cfg=lynx.cfg http://the.site.com/login

After you input the username and password, and select 'preserve me on this pc' or something similar. If login successfully, you will see a beautiful text web page of the site. And you logout. The in the current directory, you will find a cookie file named as cookie.file. This is what we need for wget.

Then wget can download file from the site with this command.

wget --load-cookies ./cookie.file http://the.site.com/download/we-can-make-this-world-better.tar.gz

I use this chrome extension. It'll give you the wget command for any download link you open.

You can install this plugin in Firefox: https://addons.mozilla.org/en-US/firefox/addon/cliget/?src=cb-dl-toprated Start downloading what you want and click on the plugin. It gives you the whole command either for wget or curl to download the file on the serer. Very easy!