Fetching a URL with HTTP

The HyperText Transport Protocol (HTTP) is the protocol used on the World Wide Web. This section presents a procedure to fetch pages or images from a server on the Web. Items in the Web are identified with a Universal Resource Location (URL) that specifies a host, port, and location on the host. The basic outline of HTTP is that a client sends a URL to a server, and the server responds with some header information and some content data. The header information describes the content, which can be hypertext, images, postscript, and more.

Example 17-5 Opening a connection to an HTTP server.
 proc Http_Open {url} { global http if {![regexp -nocase {^(http://)?([^:/]+)(:([0-9])+)?(/.*)}\ $url x protocol server y port path]} ...

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