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author | Pádraig Brady <P@draigBrady.com> | 2010-10-26 17:55:10 +0100 |
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committer | Pádraig Brady <P@draigBrady.com> | 2010-10-27 11:18:51 +0100 |
commit | 883ac22239036025896ff99bd4b2a6d02712f39f (patch) | |
tree | 93bd2ebfec80b218b8fd55f144a77a4d27ce8a3d /doc | |
parent | 0d792d061e460fd5dfe6e4226f96bbc3b8788199 (diff) | |
download | coreutils-883ac22239036025896ff99bd4b2a6d02712f39f.tar.xz |
cp: make --attributes-only override --reflink completely
* doc/coreutils.texi (cp invocation): Change the description slightly
so as users might not immediately discount using this option.
Mention that --reflink is overridden by the other linking options and
--attributes-only, and give an example where this might be useful.
* src/copy.c (copy_internal): Bypass the reflink if
--attributes-only is specifed.
* tests/cp/reflink-perm: Ensure both --reflink modes are
overridden by --attributes-only.
* NEWS: Mention the change in behavior.
Reported by Jim Meyering.
Diffstat (limited to 'doc')
-rw-r--r-- | doc/coreutils.texi | 18 |
1 files changed, 13 insertions, 5 deletions
diff --git a/doc/coreutils.texi b/doc/coreutils.texi index 4d17ed18b..0b5a3d341 100644 --- a/doc/coreutils.texi +++ b/doc/coreutils.texi @@ -7614,12 +7614,11 @@ implementations that dereference symbolic links by default. @cindex COW @cindex clone @cindex copy on write -Perform a lightweight, copy-on-write (COW) copy. -Copying with this option can succeed only on some file systems. -Once it has succeeded, beware that the source and destination files -share the same disk data blocks as long as they remain unmodified. +Perform a lightweight, copy-on-write (COW) copy, if supported by the +file system. Once it has succeeded, beware that the source and destination +files share the same disk data blocks as long as they remain unmodified. Thus, if a disk I/O error affects data blocks of one of the files, -the other suffers the exact same fate. +the other suffers the same fate. The @var{when} value can be one of the following: @@ -7633,6 +7632,15 @@ If the copy-on-write operation is not supported then fall back to the standard copy behaviour. @end table +This option is overridden by the @option{--link}, @option{--symbolic-link} +and @option{--attributes-only} options, thus allowing it to be used +to configure the default data copying behavior for @command{cp}. +For example, with the following alias, @command{cp} will use the +minimum amount of space supported by the file system. + +@example +alias cp='cp --reflink=auto --sparse=always' +@end example @item --remove-destination @opindex --remove-destination |