GZIP Compression Test

The phrase may not automatically appear however, it depends on your browser. You may need to update to a later version of your browser for this to work. If you can not uncompress it, you need to install an uncompressor:

• UNIX:

  if you are using a later copy of Mosaic, then the gzip encoding type is handled automatically and you should have been able to see the above test document. If you are using Netscape 1.1, then you'll need to have the following in your /usr/lib/X11/app-defaults/Netscape file:

  *encodingFilters:                                 \
          x-compress :  : .Z     : uncompress -c  \n\
          x-gzip     :  : .z,.gz : gzip -cdq      \n
  

  
  
  

  If, on the other hand, you would prefer to manually view the GZIP'd file, then you will want to add the following entry to your mailcap file:
  

  application/x-gzip; gzip -d %s
  

  where gzip is a GZIP uncompressor.

  You may quickly get a copy of gzip-1.2.4.tar for UNIX systems. Note that this copy may not be as recent as the previous reference however.

  
  

• PCs:

  There are several Windows(TM) based GZIP uncompressors available. The syntax is as follows for Mosaic.ini:
  
  

  [Viewers]
  TYPE17=application/x-gzip          <-- the next sequential TYPE number in your list
  application/x-gzip=gzip -d %s      <-- you may need to supply the complete path
  [Suffixes]
  application/x-gzip=.gz
  

  where gzip and winzip are some of the many GZIP uncompressors.

  You may quickly get a copy of gzip-124.exe for DOS or winzip56.exe for Windows. Note that this copy may not be as recent as the previous reference however.
  

  
  

• Mac:

  There are several Mac based GZIP uncompressors available. MacGZIP is one of many GZIP uncompressors.
  
  You may quickly get a copy of:

  MacGzip_FAT_1.0.cpt

  MacGzip_PPC_1.0.cpt

  MacGzip_68K_1.0.cpt

  MacGzip_68ktc_1.0.cpt

  for the Macintosh. The original site for MacGZip is ftp://ftp.cps.unizar.es/pub/mac/SPDsoft but access times are quite slow.

  Note that these copies may not be as recent as the previous reference however.

  Thanks go to J.A. Gutierrez for these pointers.
  
  To install the software:
  

  Get the program from one of the above sources. Then run DeHQX to remove the .hqx extension. You will now have a program. In Mosaic, open the Preferences dialog box and add the application to the Helper Application entry box. The MIME type is ``application'', the subtype is ``x-gzip'', and the extension is ``gz''.

  
  
  

Note to server authors: For those wishing to serve gzip'd files, note these comments from Brian Behlendorf:

This is still a little ``predictive'' but I think this is the way it should be.

If you are putting up compressed files on your web site you need to add a Content-Encoding line which tells the browser to uncompress it. Using the Free Software Foundation's GNU zip tools seems like the only viable cross platform option.

For Apache and NCSA's httpd, add the following line to srm.conf (usually /usr/local/etc/httpd/conf/srm.conf) , and any file like *.wrl.gz will be properly labeled with Content-encoding: x-gzip

AddEncoding     x-gzip  gz




For CERN, it is just a little different... (in httpd.conf)

AddEncoding     .gz     x-gzip

Thanks go to Roman Czyborra (czyborra@cs.tu-berlin.de) for his efforts in getting this type registered.

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