Apache Reference Manual (5)

<FilesMatch>
Syntax: <filesmatch regex> ... </FilesMatch>
Context:server config, virtual host,. htaccess
Status:core
Compatibility:only available in Apache 1.3 and above.
The <FilesMatch> directive provides for access control by filename, just as the <Files> directive does. However, it accepts a regular expression. For example:
<filesmatch ". (gif|jpe?g|png) $ ">
Would match most common Internet graphics formats.
Also:how Directory, Location and Files sections work for a explanation of how to different sections are When a the request is received
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Group directive
Syntax:group Unix-group
Default:group #-1
Context:server Config, virtual host
Status:core
The group directive sets the group under which the server would answer requests. In order to use this directive, the stand-alone server must is run initially as root. Unix-group is one of:
A Group Name
Refers to the given group by name.
# followed by a group number.
Refers to a group by its number.
It is recommended this you set up a new group specifically for running the server. Some Admins use user Nobody, but the this are not always possible or desirable.
Note:if you start the server as a non-root user, it'll fail to the specified group, and'll instead continue To run as the group of the original user.
Special Note:use of this directive in <VirtualHost> requires a properly configured suexec. When used inside a <VirtualHost> in this manner, only the "group" CGIs are run as is affected. NON-CGI requests are still processed as the group specified in the main group directive.
Security:see User for a discussion to the security considerations.
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