.\" Copyright 2000 Andreas Dilger (adilger@turbolinux.com)
.\"
.\" This man page was created for blkid from e2fsprogs-1.25.
-.\"
+.\"
.\" This file may be copied under the terms of the GNU Public License.
-.\"
+.\"
.\" Based on uuidgen, Mon Sep 17 10:42:12 2000, Andreas Dilger
.TH BLKID 8 "@E2FSPROGS_MONTH@ @E2FSPROGS_YEAR@" "E2fsprogs version @E2FSPROGS_VERSION@"
.SH NAME
blkid \- command\-line utility to locate/print block device attributes
.SH SYNOPSIS
-.B blkid
+.B blkid
[
-.B \-hv
+.B \-ghlLv
]
[
[
The
.B blkid
program is the command-line interface to working with
-.BR libuuid (3)
-library. It can determine the type of content (e.g. filesystem, swap)
+.BR libblkid (3)
+library. It can determine the type of content (e.g. filesystem, swap)
a block device holds, and also attributes (tokens, NAME=value pairs)
from the content metadata (e.g. LABEL or UUID fields).
.PP
more devices.
.SH OPTIONS
.TP
-.B \-c
+.BI \-c " cachefile"
Read from
.I cachefile
instead of reading from the default cache file
.IR /etc/blkid.tab .
If you want to start with a clean cache (i.e. don't report devices previously
scanned but not necessarily available at this time), specify
-.IR /dev/null.
+.IR /dev/null .
+.TP
+.B \-g
+Perform a garbage collection pass on the blkid cache to remove
+devices which no longer exist.
.TP
.B \-h
Display a usage message and exit.
.TP
-.B \-o
-Display
+.B \-l
+Look up one device that matches the search parameter specified using
+the
+.B \-t
+option. If there are multiple devices that match the specified search
+parameter, then the device with the highest priority is returned, and/or
+the first device found at a given priority. Device types in order of
+decreasing priority are Device Mapper, EVMS, LVM, MD, and finally regular
+block devices. If this option is not specified,
+.B blkid
+will print all of the devices that match the search parameter.
+.TP
+.BI \-o " format"
+Display
.BR blkid 's
output using the specified format. The
.I format
-parameter may be
-.IR full ,
-(the default),
-.IR value ,
-(only print the value of any tags printed by
-.BR blkid)
-or
+parameter may be
+.I full
+(the default),
+.I value
+(only print the value of the tags),
+.I list
+(print the devices in a user-friendly format),
+or
.I device
(only print the device name).
.TP
-.B \-s
-Show only the tags for each (specified) device that match
+.B \-L
+Print the devices in a user-friendly list format. This is the
+equivalent of using the option \fB-o list\fR.
+.TP
+.BI \-s " tag"
+For each (specified) device, show only the tags that match
.IR tag .
It is possible to specify multiple
-.B \-s
+.B \-s
options. If no tag is specified, then all tokens are shown for all
(specified) devices.
-In order to just refresh the cache without showing any tokens use
+In order to just refresh the cache without showing any tokens, use
.B "-s none"
with no other options.
.TP
-.B \-t
-Search the blkid cache (plus any devices specifed on the command line)
-for all visible block devices with tokens named
+.BI \-t " NAME" = "value"
+Search for block devices with tokens named
.I NAME
-that have the value
+that have the value
.IR value ,
-and print the name of any devices that are found.
+and display any devices which are found.
Common values for
.I NAME
include
.BR LABEL ,
and
.BR UUID .
+If there are no devices specified on the command line, all block devices
+will be searched; otherwise only the specified devices are searched.
.TP
.B \-v
Display version number and exit.
.TP
-.B \-w
-.I <writecachefile>
+.BI \-w " writecachefile"
Write the device cache to
.I writecachefile
instead of writing it to the default cache file
If you don't want to save the cache to the default file, specify
.IR /dev/null.
If not specified it will be the same file as that given by the
-.B -c
+.B \-c
option.
.TP
-.I <device>
+.I device
Display tokens from only the specified device. It is possible to
give multiple
-.I <device>
+.I device
options on the command line. If none is given, all devices which
appear in
.I /proc/partitions
are shown, if they are recognized.
.SH "RETURN CODE"
If the specified token was found, or if any tags were shown from (specified)
-devices 0 is returned. If the specified token was not found, or no
-(specified) devices could be identified, an exit code of 2 is returned.
+devices, 0 is returned. If the specified token was not found, or no
+(specified) devices could be identified, an exit code of 2 is returned.
For usage or other errors, an exit code of 4 is returned.
.SH AUTHOR
.B blkid
git://git.whamcloud.com / tools / e2fsprogs.git / blobdiff