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Diffstat (limited to 'man2/ioctl_iflags.2')
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diff --git a/man2/ioctl_iflags.2 b/man2/ioctl_iflags.2 deleted file mode 100644 index cf4962829..000000000 --- a/man2/ioctl_iflags.2 +++ /dev/null @@ -1,202 +0,0 @@ -.\" Copyright (c) 2017 by Michael Kerrisk <mtk.manpages@gmail.com> -.\" -.\" SPDX-License-Identifier: Linux-man-pages-copyleft -.\" -.\" -.TH ioctl_iflags 2 (date) "Linux man-pages (unreleased)" -.SH NAME -ioctl_iflags \- ioctl() operations for inode flags -.SH DESCRIPTION -Various Linux filesystems support the notion of -.IR "inode flags" \[em]attributes -that modify the semantics of files and directories. -These flags can be retrieved and modified using two -.BR ioctl (2) -operations: -.PP -.in +4n -.EX -int attr; -fd = open("pathname", ...); -\& -ioctl(fd, FS_IOC_GETFLAGS, &attr); /* Place current flags - in \[aq]attr\[aq] */ -attr |= FS_NOATIME_FL; /* Tweak returned bit mask */ -ioctl(fd, FS_IOC_SETFLAGS, &attr); /* Update flags for inode - referred to by \[aq]fd\[aq] */ -.EE -.in -.PP -The -.BR lsattr (1) -and -.BR chattr (1) -shell commands provide interfaces to these two operations, -allowing a user to view and modify the inode flags associated with a file. -.PP -The following flags are supported -(shown along with the corresponding letter used to indicate the flag by -.BR lsattr (1) -and -.BR chattr (1)): -.TP -.BR FS_APPEND_FL " \[aq]a\[aq]" -The file can be opened only with the -.B O_APPEND -flag. -(This restriction applies even to the superuser.) -Only a privileged process -.RB ( CAP_LINUX_IMMUTABLE ) -can set or clear this attribute. -.TP -.BR FS_COMPR_FL " \[aq]c\[aq]" -Store the file in a compressed format on disk. -This flag is -.I not -supported by most of the mainstream filesystem implementations; -one exception is -.BR btrfs (5). -.TP -.BR FS_DIRSYNC_FL " \[aq]D\[aq] (since Linux 2.6.0)" -Write directory changes synchronously to disk. -This flag provides semantics equivalent to the -.BR mount (2) -.B MS_DIRSYNC -option, but on a per-directory basis. -This flag can be applied only to directories. -.\" .TP -.\" .BR FS_EXTENT_FL " \[aq]e\[aq]" -.\" FIXME Some support on ext4? (EXT4_EXTENTS_FL) -.TP -.BR FS_IMMUTABLE_FL " \[aq]i\[aq]" -The file is immutable: -no changes are permitted to the file contents or metadata -(permissions, timestamps, ownership, link count, and so on). -(This restriction applies even to the superuser.) -Only a privileged process -.RB ( CAP_LINUX_IMMUTABLE ) -can set or clear this attribute. -.TP -.BR FS_JOURNAL_DATA_FL " \[aq]j\[aq]" -Enable journaling of file data on -.BR ext3 (5) -and -.BR ext4 (5) -filesystems. -On a filesystem that is journaling in -.I ordered -or -.I writeback -mode, a privileged -.RB ( CAP_SYS_RESOURCE ) -process can set this flag to enable journaling of data updates on -a per-file basis. -.TP -.BR FS_NOATIME_FL " \[aq]A\[aq]" -Don't update the file last access time when the file is accessed. -This can provide I/O performance benefits for applications that do not care -about the accuracy of this timestamp. -This flag provides functionality similar to the -.BR mount (2) -.B MS_NOATIME -flag, but on a per-file basis. -.\" .TP -.\" .BR FS_NOCOMP_FL " \[aq]\[aq]" -.\" FIXME Support for FS_NOCOMP_FL on Btrfs? -.TP -.BR FS_NOCOW_FL " \[aq]C\[aq] (since Linux 2.6.39)" -The file will not be subject to copy-on-write updates. -This flag has an effect only on filesystems that support copy-on-write -semantics, such as Btrfs. -See -.BR chattr (1) -and -.BR btrfs (5). -.TP -.BR FS_NODUMP_FL " \[aq]d\[aq]" -Don't include this file in backups made using -.BR dump (8). -.TP -.BR FS_NOTAIL_FL " \[aq]t\[aq]" -This flag is supported only on Reiserfs. -It disables the Reiserfs tail-packing feature, -which tries to pack small files (and the final fragment of larger files) -into the same disk block as the file metadata. -.TP -.BR FS_PROJINHERIT_FL " \[aq]P\[aq] (since Linux 4.5)" -.\" commit 040cb3786d9b25293b8b0b05b90da0f871e1eb9b -.\" Flag name was added in Linux 4.4 -.\" FIXME Not currently supported because not in FS_FL_USER_MODIFIABLE? -Inherit the quota project ID. -Files and subdirectories will inherit the project ID of the directory. -This flag can be applied only to directories. -.TP -.BR FS_SECRM_FL " \[aq]s\[aq]" -Mark the file for secure deletion. -This feature is not implemented by any filesystem, -since the task of securely erasing a file from a recording medium -is surprisingly difficult. -.TP -.BR FS_SYNC_FL " \[aq]S\[aq]" -Make file updates synchronous. -For files, this makes all writes synchronous -(as though all opens of the file were with the -.B O_SYNC -flag). -For directories, this has the same effect as the -.B FS_DIRSYNC_FL -flag. -.TP -.BR FS_TOPDIR_FL " \[aq]T\[aq]" -Mark a directory for special treatment under the Orlov block-allocation -strategy. -See -.BR chattr (1) -for details. -This flag can be applied only to directories and -has an effect only for ext2, ext3, and ext4. -.TP -.BR FS_UNRM_FL " \[aq]u\[aq]" -Allow the file to be undeleted if it is deleted. -This feature is not implemented by any filesystem, -since it is possible to implement file-recovery mechanisms outside the kernel. -.PP -In most cases, -when any of the above flags is set on a directory, -the flag is inherited by files and subdirectories -created inside that directory. -Exceptions include -.BR FS_TOPDIR_FL , -which is not inheritable, and -.BR FS_DIRSYNC_FL , -which is inherited only by subdirectories. -.SH STANDARDS -Linux. -.SH NOTES -In order to change the inode flags of a file using the -.B FS_IOC_SETFLAGS -operation, -the effective user ID of the caller must match the owner of the file, -or the caller must have the -.B CAP_FOWNER -capability. -.PP -The type of the argument given to the -.B FS_IOC_GETFLAGS -and -.B FS_IOC_SETFLAGS -operations is -.IR int\~* , -notwithstanding the implication in the kernel source file -.I include/uapi/linux/fs.h -that the argument is -.IR long\~* . -.SH SEE ALSO -.BR chattr (1), -.BR lsattr (1), -.BR mount (2), -.BR btrfs (5), -.BR ext4 (5), -.BR xfs (5), -.BR xattr (7), -.BR mount (8) |