nbdkit-gzip-filter(1)

1nbdkit-gzip-filter(1)               NBDKIT               nbdkit-gzip-filter(1)
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NAME

6       nbdkit-gzip-filter - decompress a .gz file
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SYNOPSIS

9        nbdkit file --filter=gzip FILENAME.gz
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DESCRIPTION

12       "nbdkit-gzip-filter" is a filter for nbdkit(1) which transparently
13       decompresses a gzip-compressed file.  You can place this filter on top
14       of nbdkit-file-plugin(1) to decompress a local .gz file, or on top of
15       other plugins such as nbdkit-curl-plugin(1):
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17        nbdkit curl --filter=gzip https://example.com/disk.gz
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19       With nbdkit-tar-filter(1) it can be used to extract files from a
20       compressed tar file:
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22        nbdkit curl --filter=tar --filter=gzip \
23               https://example.com/file.tar.gz tar-entry=disk.img
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25       The filter only allows read-only connections.
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27       Note that gzip files are not very good for random access in large files
28       because seeking to a position in the gzip file involves decompressing
29       all data before that point in the file.  A more practical method to
30       compress large disk images is to use the xz(1) format and
31       nbdkit-xz-filter(1).
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33       To allow seeking this filter has to keep the contents of the complete
34       uncompressed file, which it does in a hidden temporary file under
35       $TMPDIR.
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PARAMETERS

38       There are no parameters specific to this plugin.
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ENVIRONMENT VARIABLES

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

48       $filterdir/nbdkit-gzip-filter.so
49           The plugin.
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51           Use "nbdkit --dump-config" to find the location of $filterdir.
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VERSION

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

62       Richard W.M. Jones
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COPYRIGHT

65       Copyright (C) 2013-2020 Red Hat Inc.
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LICENSE

68       Redistribution and use in source and binary forms, with or without
69       modification, are permitted provided that the following conditions are
70       met:
71
72       •   Redistributions of source code must retain the above copyright
73           notice, this list of conditions and the following disclaimer.
74
75       •   Redistributions in binary form must reproduce the above copyright
76           notice, this list of conditions and the following disclaimer in the
77           documentation and/or other materials provided with the
78           distribution.
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80       •   Neither the name of Red Hat nor the names of its contributors may
81           be used to endorse or promote products derived from this software
82           without specific prior written permission.
83
84       THIS SOFTWARE IS PROVIDED BY RED HAT AND CONTRIBUTORS ''AS IS'' AND ANY
85       EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
86       IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
87       PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT OR CONTRIBUTORS BE
88       LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
89       CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
90       SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
91       BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
92       WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
93       OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
94       ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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98nbdkit-1.32.5                     2023-01-03             nbdkit-gzip-filter(1)