Introduction to the Apache Web Server - ApacheCon

7.4.3 mod gzip
More will be said about mod gzip later. Files are compressed as they are sent out to the client, and an
additional Content-Encoding header is attached to the file to let the browser know that the content needs
to be decoded (uncompressed) before it can be displayed.
7.5 Language
• Content-Language header specifies the language that is being sent
• Browser configuration can determine the preferred language (See Content Negotiation)
• Can be set in addition to other attributes
7.6 Multiple file extensions
Files can have more than one file extension in order to convey more than one of the above pieces of information.
file.tar.gz.en
file.tar.Z.fr
file.html.gz.de
There’s no great value of going into much detail here with the language stuff, as we will get into much greater
depth in the Content Negotiation section, which is just a few down the line.
You may also wish to make a note that multiple file extensions conveying the same piece of information will
cause all but the last one to be ignored. Thus file.doc.tar.txt is a text file, not a doc or tar file.
7.7 Experiment
• In your vhost directory, create a file called something.abc
• Add a MIME type to this file extension
• Verify that your browser loads it with this MIME type, and asks you what it is supposed to do with
it.
The purpose of this exercise is to illustrate that you can make up your own file types, and cause the browser
to behave a certain way upon receiving that file type. This is how people come up with custom plug ins, file
handlers, or whatever. You have some client-side application that gets mapped to a particular MIME type
header.
Note also that Internet Explorer occasionally thinks that it is smarter than you. That is, it will, in some conditions,
follow the file extension rather than the MIME type. Thus, a txt file with an Application/Unknown
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