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4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk This module is contained in the mod_mime_magic.c file, and is
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk an optional extension to the Apache HTTPD server.
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk It can be used to determine the MIME type of a file by looking at a
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk few bytes of its contents, the same way the Unix file(1) command works.
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk To use mod_mime_magic you have to enable the following line in the
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk This should be listed <EM>before</EM> mod_mime in the build
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk <TT>Configuration</TT> file so that it will be used after mod_mime.
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk mod_mime_magic is intended as a "second line of defense" for cases
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk mod_mime cannot resolve.
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk This module is derived from a free version of the <CODE>file(1)</CODE>
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk command for Unix,
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk which uses "magic numbers" and other hints from a file's contents to
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk figure out what the contents are.
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk In the case of this module,
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk it tries to figure out the MIME type of the file.
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk This module active only if the magic file is specified by the
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk <A HREF="#mimemagicfile"><CODE>MimeMagicFile</CODE></A> directive.
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk The contents of the file are plain ASCII text in 4-5 columns.
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk Blank lines are allowed but ignored.
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk Commented lines use a hash mark "#".
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk The remaining lines are parsed for the following columns:
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk <TD>byte number to begin checking from
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk ">" indicates a dependency upon the previous non-">" line</TD>
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk <TD>type of data to match
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk <TR><TD>short</TD><TD>machine-order 16-bit integer</TD></TR>
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk <TR><TD>long</TD><TD>machine-order 32-bit integer</TD></TR>
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk <TR><TD>string</TD><TD>arbitrary-length string</TD></TR>
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk <TR><TD>beshort</TD><TD>big-endian 16-bit integer</TD></TR>
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk <TR><TD>belong</TD><TD>big-endian 32-bit integer</TD></TR>
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk <TR><TD>bedate</TD><TD>big-endian 32-bit integer date</TD></TR>
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk <TR><TD>leshort</TD><TD>little-endian 16-bit integer</TD></TR>
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk <TR><TD>lelong</TD><TD>little-endian 32-bit integer</TD></TR>
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk <TR><TD>ledate</TD><TD>little-endian 32-bit integer date</TD></TR>
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk For example, the following magic file lines
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk would recognize some audio formats.
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk0 string .snd
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk Or these would recognize the difference between "*.doc" files containing
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk Microsoft Word or FrameMaker documents. (These are incompatible file
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk formats which use the same file suffix.)
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk0 string \<MakerDictionary application/x-frame
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk0 string \320\317\021\340\241\261 application/msword
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk An optional MIME encoding can be included as a fifth column.
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk For example, this can recognize gzipped files and set the encoding
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk# gzip (GNU zip, not to be confused with [Info-ZIP/PKWARE] zip archiver)
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk0 string \037\213 application/octet-stream x-gzip
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk This module is not for every system. If your system is barely keeping
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk up with its load or if you're performing a web server benchmark,
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk you may not want to enable this because the processing is not free.
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk However, an effort was made to improve the performance of the original
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk file(1) code to make it fit in a busy web server.
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk It was designed for a server where there are thousands of users who
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk publish their own documents.
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk This is probably very common on intranets.
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk Many times, it's helpful
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk if the server can make more intelligent decisions about a file's
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk contents than the file name allows
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk ...even if just to reduce the "why doesn't my page work" calls
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk when users improperly name their own files.
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk You have to decide if the extra work suits your environment.
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk When compiling an Apache server, this module should be at or near the
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk top of the list of modules in the Configuration file. The modules are
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk listed in increasing priority so that will mean this one is used only
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk as a last resort, just like it was designed to.
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk MimeMagicFile
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk <STRONG>Syntax:</STRONG> MimeMagicFile <EM>magic-file-name</EM>
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk <STRONG>Context:</STRONG> server config, virtual host
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk The <CODE>MimeMagicFile</CODE> directive can be used to enable this module,
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk the default file is distributed at <CODE>conf/magic</CODE>.
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk Non-rooted paths are relative to the ServerRoot. Virtual hosts
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk will use the same file as the main server unless a more specific setting
4b8d88eb610aa1e0bb6ec632f792744b3d6b5f22jeff.schenk is used, in which case the more specific setting overrides the main server's
* originally posted to comp.sources.unix. Copyright info for that program
* routines. (i.e. usually for logging, files, or memory allocation in