*-z*, *--zero-range*::
Zeroes space in the byte range starting at _offset_ and continuing for _length_ bytes. Within the specified range, blocks are preallocated for the regions that span the holes in the file. After a successful call, subsequent reads from this range will return zeroes.
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-Zeroing is done within the filesystem preferably by converting the range into unwritten extents. This approach means that the specified range will not be physically zeroed out on the device (except for partial blocks at the either end of the range), and I/O is (otherwise) required only to update metadata.
+Zeroing is done within the filesystem preferably by converting the range into unwritten extents. This approach means that the specified range will not be physically zeroed out on the device (except for partial blocks at either end of the range), and I/O is (otherwise) required only to update metadata.
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Option *--keep-size* can be specified to prevent file length modification.
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Zeroing is done within the filesystem. The filesystem may use a hardware-accelerated zeroing command or may submit regular writes. The behavior depends on the filesystem design and the available hardware.
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-Options *--keep-size* cannot be specified for the write-zeroes operation because allocating written blocks beyond the inode size is not permitted.
+Option *--keep-size* cannot be specified for the write-zeroes operation because allocating written blocks beyond the inode size is not permitted.
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