1 .\" Copyright (c) 2018, Red Hat, Inc. All rights reserved.
3 .\" SPDX-License-Identifier: GPL-2.0-or-later
4 .TH ioctl_fslabel 2 (date) "Linux man-pages (unreleased)"
6 ioctl_fslabel \- get or set a filesystem label
12 .BR "#include <linux/fs.h>" " /* Definition of " *FSLABEL* " constants */"
13 .B #include <sys/ioctl.h>
15 .BI "int ioctl(int " fd ", FS_IOC_GETFSLABEL, char " label [FSLABEL_MAX]);
16 .BI "int ioctl(int " fd ", FS_IOC_SETFSLABEL, char " label [FSLABEL_MAX]);
19 If a filesystem supports online label manipulation, these
21 operations can be used to get or set the filesystem label for the filesystem
27 operation requires privilege
28 .RB ( CAP_SYS_ADMIN ).
30 On success zero is returned.
31 On error, \-1 is returned, and
33 is set to indicate the error.
35 Possible errors include (but are not limited to) the following:
39 references an inaccessible memory area.
42 The specified label exceeds the maximum label length for the filesystem.
45 This can appear if the filesystem does not support online label manipulation.
48 The calling process does not have sufficient permissions to set the label.
54 They were previously known as
55 .B BTRFS_IOC_GET_FSLABEL
57 .B BTRFS_IOC_SET_FSLABEL
58 and were private to Btrfs.
60 The maximum string length for this interface is
62 including the terminating null byte (\[aq]\\0\[aq]).
63 Filesystems have differing maximum label lengths, which may or
64 may not include the terminating null.
65 The string provided to
67 must always be null-terminated, and the string returned by
69 will always be null-terminated.