NAME

       nbdkit-gzip-filter - decompress a .gz file

SYNOPSIS

        nbdkit file --filter=gzip FILENAME.gz

DESCRIPTION

       "nbdkit-gzip-filter" is a filter for nbdkit(1) which transparently decompresses a gzip-
       compressed file.  You can place this filter on top of nbdkit-file-plugin(1) to decompress
       a local .gz file, or on top of other plugins such as nbdkit-curl-plugin(1):

        nbdkit curl --filter=gzip https://example.com/disk.gz

       With nbdkit-tar-filter(1) it can be used to extract files from a compressed tar file:

        nbdkit curl --filter=tar --filter=gzip \
               https://example.com/file.tar.gz tar-entry=disk.img

       The filter only allows read-only connections.

       Note that gzip files are not very good for random access in large files because seeking to
       a position in the gzip file involves decompressing all data before that point in the file.
       A more practical method to compress large disk images is to use the xz(1) format and
       nbdkit-xz-filter(1).

       To allow seeking this filter has to keep the contents of the complete uncompressed file,
       which it does in a hidden temporary file under $TMPDIR.

PARAMETERS

       There are no parameters specific to this plugin.

ENVIRONMENT VARIABLES

       "TMPDIR"
           Because the gzip format is not seekable, this filter has to store the complete
           contents of the compressed file in a temporary file located in /var/tmp by default.
           You can override this location by setting the "TMPDIR" environment variable before
           starting nbdkit.

FILES

       $filterdir/nbdkit-gzip-filter.so
           The plugin.

           Use "nbdkit --dump-config" to find the location of $filterdir.

VERSION

       "nbdkit-gzip-filter" first appeared in nbdkit 1.22.  It is derived from
       "nbdkit-gzip-plugin" which first appeared in nbdkit 1.0.

SEE ALSO

       nbdkit-curl-plugin(1), nbdkit-file-plugin(1), nbdkit-tar-filter(1), nbdkit-xz-filter(1),
       nbdkit(1), nbdkit-plugin(3).

AUTHORS

       Richard W.M. Jones

COPYRIGHT

       Copyright (C) 2013-2020 Red Hat Inc.

LICENSE

       Redistribution and use in source and binary forms, with or without modification, are
       permitted provided that the following conditions are met:

       •   Redistributions of source code must retain the above copyright notice, this list of
           conditions and the following disclaimer.

       •   Redistributions in binary form must reproduce the above copyright notice, this list of
           conditions and the following disclaimer in the documentation and/or other materials
           provided with the distribution.

       •   Neither the name of Red Hat nor the names of its contributors may be used to endorse
           or promote products derived from this software without specific prior written
           permission.

       THIS SOFTWARE IS PROVIDED BY RED HAT AND CONTRIBUTORS ''AS IS'' AND ANY EXPRESS OR IMPLIED
       WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
       FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT OR CONTRIBUTORS
       BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
       DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
       OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
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