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Diffstat (limited to 'man2/ioctl_ficlonerange.2')
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diff --git a/man2/ioctl_ficlonerange.2 b/man2/ioctl_ficlonerange.2 deleted file mode 100644 index b2c5e6b..0000000 --- a/man2/ioctl_ficlonerange.2 +++ /dev/null @@ -1,129 +0,0 @@ -.\" Copyright (c) 2016, Oracle. All rights reserved. -.\" -.\" SPDX-License-Identifier: GPL-2.0-or-later -.TH ioctl_ficlonerange 2 2023-10-31 "Linux man-pages 6.7" -.SH NAME -ioctl_ficlonerange, ioctl_ficlone \- -share some the data of one file with another file -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.SH SYNOPSIS -.nf -.BR "#include <linux/fs.h>" " /* Definition of " FICLONE* " constants */" -.B #include <sys/ioctl.h> -.P -.BI "int ioctl(int " dest_fd ", FICLONERANGE, struct file_clone_range *" arg ); -.BI "int ioctl(int " dest_fd ", FICLONE, int " src_fd ); -.fi -.SH DESCRIPTION -If a filesystem supports files sharing physical storage between multiple -files ("reflink"), this -.BR ioctl (2) -operation can be used to make some of the data in the -.I src_fd -file appear in the -.I dest_fd -file by sharing the underlying storage, which is faster than making a separate -physical copy of the data. -Both files must reside within the same filesystem. -If a file write should occur to a shared region, -the filesystem must ensure that the changes remain private to the file being -written. -This behavior is commonly referred to as "copy on write". -.P -This ioctl reflinks up to -.I src_length -bytes from file descriptor -.I src_fd -at offset -.I src_offset -into the file -.I dest_fd -at offset -.IR dest_offset , -provided that both are files. -If -.I src_length -is zero, the ioctl reflinks to the end of the source file. -This information is conveyed in a structure of -the following form: -.P -.in +4n -.EX -struct file_clone_range { - __s64 src_fd; - __u64 src_offset; - __u64 src_length; - __u64 dest_offset; -}; -.EE -.in -.P -Clones are atomic with regards to concurrent writes, so no locks need to be -taken to obtain a consistent cloned copy. -.P -The -.B FICLONE -ioctl clones entire files. -.SH RETURN VALUE -On error, \-1 is returned, and -.I errno -is set to indicate the error. -.SH ERRORS -Error codes can be one of, but are not limited to, the following: -.TP -.B EBADF -.I src_fd -is not open for reading; -.I dest_fd -is not open for writing or is open for append-only writes; -or the filesystem which -.I src_fd -resides on does not support reflink. -.TP -.B EINVAL -The filesystem does not support reflinking the ranges of the given files. -This error can also appear if either file descriptor represents -a device, FIFO, or socket. -Disk filesystems generally require the offset and length arguments -to be aligned to the fundamental block size. -XFS and Btrfs do not support -overlapping reflink ranges in the same file. -.TP -.B EISDIR -One of the files is a directory and the filesystem does not support shared -regions in directories. -.TP -.B EOPNOTSUPP -This can appear if the filesystem does not support reflinking either file -descriptor, or if either file descriptor refers to special inodes. -.TP -.B EPERM -.I dest_fd -is immutable. -.TP -.B ETXTBSY -One of the files is a swap file. -Swap files cannot share storage. -.TP -.B EXDEV -.IR dest_fd " and " src_fd -are not on the same mounted filesystem. -.SH STANDARDS -Linux. -.SH HISTORY -Linux 4.5. -.P -They were previously known as -.B BTRFS_IOC_CLONE -and -.BR BTRFS_IOC_CLONE_RANGE , -and were private to Btrfs. -.SH NOTES -Because a copy-on-write operation requires the allocation of new storage, the -.BR fallocate (2) -operation may unshare shared blocks to guarantee that subsequent writes will -not fail because of lack of disk space. -.SH SEE ALSO -.BR ioctl (2) |