1 .\" Copyright 2000 Andreas Dilger (adilger@turbolinux.com)
3 .\" This man page was created for blkid from e2fsprogs-1.25.
5 .\" This file may be copied under the terms of the GNU Public License.
7 .\" Based on uuidgen, Mon Sep 17 10:42:12 2000, Andreas Dilger
8 .TH BLKID 8 "@E2FSPROGS_MONTH@ @E2FSPROGS_YEAR@" "E2fsprogs version @E2FSPROGS_VERSION@"
10 blkid \- command\-line utility to locate/print block device attributes
42 program is the command-line interface to working with
44 library. It can determine the type of content (e.g. file system, swap)
45 a block device holds, and also attributes (tokens, NAME=value pairs)
46 from the content metadata (e.g. LABEL or UUID fields).
49 has two main forms of operation: either searching for a device with a
50 specific NAME=value pair, or displaying NAME=value pairs for one or
57 instead of reading from the default cache file
59 If you want to start with a clean cache (i.e. don't report devices previously
60 scanned but not necessarily available at this time), specify
64 Perform a garbage collection pass on the blkid cache to remove
65 devices which no longer exist.
68 Display a usage message and exit.
71 Look up one device that matches the search parameter specified using
74 option. If there are multiple devices that match the specified search
75 parameter, then the device with the highest priority is returned, and/or
76 the first device found at a given priority. Device types in order of
77 decreasing priority are Device Mapper, EVMS, LVM, MD, and finally regular
78 block devices. If this option is not specified,
80 will print all of the devices that match the search parameter.
85 output using the specified format. The
91 (only print the value of the tags),
93 (print the devices in a user-friendly format),
96 (only print the device name).
99 Print the devices in a user-friendly list format. This is the
100 equivalent of using the option \fB-o list\fR.
103 For each (specified) device, show only the tags that match
105 It is possible to specify multiple
107 options. If no tag is specified, then all tokens are shown for all
109 In order to just refresh the cache without showing any tokens, use
111 with no other options.
113 .BI \-t " NAME" = "value"
114 Search for block devices with tokens named
118 and display any devices which are found.
126 If there are no devices specified on the command line, all block devices
127 will be searched; otherwise only the specified devices are searched.
130 Display version number and exit.
132 .BI \-w " writecachefile"
133 Write the device cache to
135 instead of writing it to the default cache file
137 If you don't want to save the cache to the default file, specify
139 If not specified it will be the same file as that given by the
144 Display tokens from only the specified device. It is possible to
147 options on the command line. If none is given, all devices which
150 are shown, if they are recognized.
152 If the specified token was found, or if any tags were shown from (specified)
153 devices, 0 is returned. If the specified token was not found, or no
154 (specified) devices could be identified, an exit code of 2 is returned.
155 For usage or other errors, an exit code of 4 is returned.
158 was written by Andreas Dilger for libblkid.
161 is part the e2fsprogs package since version 1.26 and is available from
162 http://e2fsprogs.sourceforge.net.