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+.\" Copyright 2001 Andreas Dilger (adilger@turbolinux.com)
+.\"
+.\" This man page was created for libblkid.so.1.0 from e2fsprogs-1.24.
+.\"
+.\" This file may be copied under the terms of the GNU Lesser General Public
+.\" License.
+.\"
+.\" Created Wed Sep 14 12:02:12 2001, Andreas Dilger
+.TH LIBBLKID 3 "May 2009" "util-linux" "Programmer's Manual"
+.SH NAME
+libblkid \- block device identification library
+.SH SYNOPSIS
+.B #include <blkid.h>
+.sp
+.B cc
+.I file.c
+.B \-lblkid
+.SH DESCRIPTION
+The
+.B libblkid
+library is used to identify block devices (disks) as to their content (e.g.
+filesystem type) as well as extracting additional information such as
+filesystem labels/volume names, unique identifiers/serial numbers.
+A common use is to allow use of LABEL= and UUID= tags instead of hard-coding
+specific block device names into configuration files.
+.P
+The low-level part of the library also allows to extract information about
+partitions and block device topology.
+.P
+The high-level part of the library keeps information about block devices in a
+cache file and is verified to still be valid before being returned to the user
+(if the user has read permission on the raw block device, otherwise not).
+The cache file also allows unprivileged users (normally anyone other
+than root, or those not in the "disk" group) to locate devices by label/id.
+The standard location of the cache file can be overridden by the
+environment variable BLKID_FILE.
+.P
+In situations where one is getting information about a single known device, it
+does not impact performance whether the cache is used or not (unless you are
+not able to read the block device directly).
+.P
+The high-level part of the library supports two methods to evaluate LABEL/UUID.
+It reads information directly from a block device or read information from
+/dev/disk/by-* udev symlinks. The udev is preferred method by default.
+.P
+If you are dealing with
+multiple devices, use of the cache is highly recommended (even if empty) as
+devices will be scanned at most one time and the on-disk cache will be
+updated if possible.
+.P
+In some cases (modular kernels), block devices are not even visible until
+after they are accessed the first time, so it is critical that there is
+some way to locate these devices without enumerating only visible devices,
+so the use of the cache file is
+.B required
+in this situation.
+.SH CONFIGURATION FILE
+The standard location of the
+.I /etc/blkid.conf
+config file can be overridden by the environment variable BLKID_CONF. For more
+details about the config file see
+.BR blkid (8)
+man page.
+.SH AUTHOR
+.B libblkid
+was written by Andreas Dilger for the ext2 filesystem utilties, with input
+from Ted Ts'o. The library was subsequently heavily modified by Ted Ts'o.
+
+The low-level probing code was rewritten by Karel Zak.
+.SH COPYING
+.B libblkid
+is available under the terms of the GNU Library General Public License (LGPL),
+version 2 (or at your discretion any later version).
+.SH "SEE ALSO"
+.BR blkid (8),
+.BR findfs (8)
+.SH AVAILABILITY
+libblkid is part of the util-linux package since version 2.15 and is available from
+ftp://ftp.kernel.org/pub/linux/utils/util-linux/.