Fallocate only zeroes space that did not previously contain data, but leaves existing data untouched. Signed-off-by: Christoph Hellwig <hch@xxxxxx> diff --git a/man2/fallocate.2 b/man2/fallocate.2 index f5c395d..f577ba8 100644 --- a/man2/fallocate.2 +++ b/man2/fallocate.2 @@ -44,8 +44,7 @@ The default operation (i.e., .I mode is zero) of .BR fallocate () -allocates and initializes to zero the disk space -within the range specified by +allocates the disk space within the range specified by .I offset and .IR len . @@ -54,6 +53,11 @@ The file size (as reported by will be changed if .IR offset + len is greater than the file size. +Any subregion withing the range specified by +.I offset +and +.IR len . +that did not contain data before the call will be initialized to zero. This default behavior closely resembles the behavior of the .BR posix_fallocate (3) library function, -- To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
