Linux – Difference between cp -r and cp -R (copy command)

cplinux

cp -r is meant to copy files recursively, and cp -R for copying directories recursively. But I've checked, and both appear to copy both files and directories, the same thing. So, what's the difference actually?

Best Answer

While -R is posix well-defined, -r is not portable!

On Linux, in the GNU and BusyBox implementations of cp, -r and -R are equivalent.

On the other side, as you can read in the POSIX manual page of cp, -r behavior is implementation-defined.

    * If  neither  the  -R  nor  -r  options were specified, cp shall take
      actions based on the type and contents of the file referenced by the
      symbolic link, and not by the symbolic link itself.

    * If the -R option was specified:

       * If  none  of  the  options  -H,  -L, nor -P were specified, it is
         unspecified which of -H, -L, or -P will be used as a default.

       * If the -H option was specified, cp shall take  actions based on
         the type and contents of the file referenced by any symbolic link
         specified as a source_file operand.

       * If the -L option was specified, cp shall take  actions based  on
         the type and contents of the file referenced by any symbolic link
         specified as a source_file operand or any symbolic links encoun-
         tered during traversal of a file hierarchy.

       * If  the  -P option was specified, cp shall copy any symbolic link
         specified as a source_file operand and any symbolic links encoun-
         tered  during traversal of a file hierarchy, and shall not follow
         any symbolic links.

    * If the -r option was  specified,  the  behavior  is implementation-
      defined.

Related Solutions

Linux Copy Command – Copy Recursively Except Hidden Directory

You could just copy everything with

cp -rf

and then delete hidden directories at the destination with

find -type d -name '.*' -and -not -name '.' -print0 | xargs -0 rm -rf

Alternatively, if you have some advanced tar (e.g. GNU tar), you could try to use tar to exclude some patterns. But I am afraid that is not possible to only exclude hidden directories, but include hidden files.

For example something like this:

tar --exclude=PATTERN -f - -c * | tar -C destination -f - -x

Btw, GNU tar has a zoo of exclude style options. My favourite is

--exclude-vcs

Linux – Difference between cp -r and cp -a

Recursive means that cp copies the contents of directories, and if a directory has subdirectories they are copied (recursively) too. Without -R, the cp command skips directories. -r is identical with -R on Linux, it differs in some edge cases on some other unix variants.

By default, cp creates a new file which has the same content as the old file, and the same permissions but restricted by the umask; the copy is dated from the time of the copy, and belongs to the user doing the copy. With the -p option, the copy has the same modification time, the same access time, and the same permissions as the original. It also has the same owner and group as the original, if the user doing the copy has the permission to create such files.

The -a option means -R and -p, plus a few other preservation options. It attempts to make a copy that's as close to the original as possible: same directory tree, same file types, same contents, same metadata (times, permissions, extended attributes, etc.).

Best Answer

Related Solutions

Linux Copy Command – Copy Recursively Except Hidden Directory

Linux – Difference between cp -r and cp -a

Related Question