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Merge pull request #11066 from infiniteregrets/cp-md
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[CI:DOCS] Update podman-cp manpage
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openshift-merge-robot authored Jul 28, 2021
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Expand Up @@ -9,112 +9,121 @@ podman\-cp - Copy files/folders between a container and the local filesystem
**podman container cp** [*options*] [*container*:]*src_path* [*container*:]*dest_path*

## DESCRIPTION
Copy the contents of **src_path** to the **dest_path**. You can copy from the container's filesystem to the local machine or the reverse, from the local filesystem to the container or between two containers.
If `-` is specified for either the SRC_PATH or DEST_PATH, you can also stream a tar archive from STDIN or to STDOUT.
**podman cp** allows copying the contents of **src_path** to the **dest_path**. Files can be copied from a container to the local machine and vice versa or between two containers.
If `-` is specified for either the `SRC_PATH` or `DEST_PATH`, one can also stream a tar archive from `STDIN` or to `STDOUT`.

The containers can be a running or stopped. The **src_path** or **dest_path** can be a file or directory.
The containers can be either running or stopped and the *src_path* or *dest_path* can be a file or directory.

The **podman cp** command assumes container paths are relative to the container's root directory (i.e., `/`).

This means supplying the initial forward slash is optional;

The command sees **compassionate_darwin:/tmp/foo/myfile.txt** and **compassionate_darwin:tmp/foo/myfile.txt** as identical.
*IMPORTANT: The **podman cp** command assumes container paths are relative to the container's root directory (`/`), which means supplying the initial forward slash is optional and therefore sees `compassionate_darwin:/tmp/foo/myfile.txt` and `compassionate_darwin:tmp/foo/myfile.txt` as identical.*

Local machine paths can be an absolute or relative value.
The command interprets a local machine's relative paths as relative to the current working directory where **podman cp** is run.

Assuming a path separator of /, a first argument of **src_path** and second argument of **dest_path**, the behavior is as follows:
Assuming a path separator of `/`, a first argument of **src_path** and second argument of **dest_path**, the behavior is as follows:

**src_path** specifies a file
**src_path** specifies a file:
- **dest_path** does not exist
- the file is saved to a file created at **dest_path** (note that parent directory must exist)
- the file is saved to a file created at **dest_path** (note that parent directory must exist).
- **dest_path** exists and is a file
- the destination is overwritten with the source file's contents
- the destination is overwritten with the source file's contents.
- **dest_path** exists and is a directory
- the file is copied into this directory using the base name from **src_path**
- the file is copied into this directory using the base name from **src_path**.

**src_path** specifies a directory
**src_path** specifies a directory:
- **dest_path** does not exist
- **dest_path** is created as a directory and the contents of the source directory are copied into this directory
- **dest_path** is created as a directory and the contents of the source directory are copied into this directory.
- **dest_path** exists and is a file
- Error condition: cannot copy a directory to a file
- Error condition: cannot copy a directory to a file.
- **dest_path** exists and is a directory
- **src_path** ends with `/`
- the source directory is copied into this directory
- the source directory is copied into this directory.
- **src_path** ends with `/.` (i.e., slash followed by dot)
- the content of the source directory is copied into this directory
- the content of the source directory is copied into this directory.

The command requires **src_path** and **dest_path** to exist according to the above rules.

If **src_path** is local and is a symbolic link, the symbolic target, is copied by default.

A colon (:) is used as a delimiter between CONTAINER and its path.
A *colon* ( : ) is used as a delimiter between a container and its path, it can also be used when specifying paths to a **src_path** or **dest_path** on a local machine, for example, `file:name.txt`.

You can also use : when specifying paths to a **src_path** or **dest_path** on a local machine, for example, `file:name.txt`.
*IMPORTANT: while using a *colon* ( : ) in a local machine path, one must be explicit with a relative or absolute path, for example: `/path/to/file:name.txt` or `./file:name.txt`*

If you use a : in a local machine path, you must be explicit with a relative or absolute path, for example:
`/path/to/file:name.txt` or `./file:name.txt`

Using `-` as the *src_path* streams the contents of STDIN as a tar archive. The command extracts the content of the tar to the *DEST_PATH* in the container. In this case, *dest_path* must specify a directory. Using `-` as the *dest_path* streams the contents of the resource (can be a directory) as a tar archive to STDOUT.
Using `-` as the **src_path** streams the contents of `STDIN` as a tar archive. The command extracts the content of the tar to the `DEST_PATH` in the container. In this case, **dest_path** must specify a directory. Using `-` as the **dest_path** streams the contents of the resource (can be a directory) as a tar archive to `STDOUT`.

Note that `podman cp` ignores permission errors when copying from a running rootless container. The TTY devices inside a rootless container are owned by the host's root user and hence cannot be read inside the container's user namespace.

## OPTIONS

#### **--archive**, **-a**
#### **--archive**, **-a**=**true** | *false*

Archive mode (copy all uid/gid information).
When set to true, files copied to a container will have changed ownership to the primary uid/gid of the container.
When set to true, files copied to a container will have changed ownership to the primary UID/GID of the container.
When set to false, maintain uid/gid from archive sources instead of changing them to the primary uid/gid of the destination container.
The default is *true*.
The default is **true**.

## ALTERNATIVES

Podman has much stronger capabilities than just `podman cp` to achieve copying files between the host and containers.

Using standard podman-mount and podman-umount takes advantage of the entire linux tool chain, rather than just cp.

If a user wants to copy contents out of a container or into a container, they can execute a few simple commands.
Using standard **[podman-mount(1)](podman-mount.1.md)** and **[podman-unmount(1)](podman-unmount.1.md)** takes advantage of the entire linux tool chain, rather than just cp.

You can copy from the container's file system to the local machine or the reverse, from the local filesystem to the container.
copying contents out of a container or into a container, can be achieved with a few simple commands. For example:

If you want to copy the /etc/foobar directory out of a container and onto /tmp on the host, you could execute the following commands:
To copy the `/etc/foobar` directory out of a container and onto `/tmp` on the host, the following commands can be executed:

mnt=$(podman mount CONTAINERID)
cp -R ${mnt}/etc/foobar /tmp
podman umount CONTAINERID

If you want to untar a tar ball into a container, you can execute these commands:
To untar a tar ball into a container, following commands can be executed:

mnt=$(podman mount CONTAINERID)
tar xf content.tgz -C ${mnt}
podman umount CONTAINERID

One last example, if you want to install a package into a container that
does not have dnf installed, you could execute something like:
To install a package into a container that
does not have dnf installed, following commands can be executed:

mnt=$(podman mount CONTAINERID)
dnf install --installroot=${mnt} httpd
chroot ${mnt} rm -rf /var/log/dnf /var/cache/dnf
podman umount CONTAINERID

This shows that using `podman mount` and `podman umount` you can use all of the
By using `podman mount` and `podman unmount`, one can use all of the
standard linux tools for moving files into and out of containers, not just
the cp command.

## EXAMPLE
## EXAMPLES

podman cp /myapp/app.conf containerID:/myapp/app.conf
- Copy a file from host to a container.
```
podman cp /myapp/app.conf containerID:/myapp/app.conf
```

podman cp /home/myuser/myfiles.tar containerID:/tmp
- Copy a file from a container to a directory on another container.
```
podman cp containerID1:/myfile.txt containerID2:/tmp
```

podman cp containerID:/myapp/ /myapp/
- Copy a directory on a container to a directory on the host.
```
podman cp containerID:/myapp/ /myapp/
```

podman cp containerID:/home/myuser/. /home/myuser/
- Copy the contents of a directory on a container to a directory on the host.
```
podman cp containerID:/home/myuser/. /home/myuser/
```

podman cp containerA:/myapp containerB:/yourapp
- Copy a directory on a container into a directory on another.
```
podman cp containerA:/myapp containerB:/yourapp
```

podman cp - containerID:/myfiles.tar.gz < myfiles.tar.gz
- Stream a tar archive from `STDIN` to a container.
```
podman cp - containerID:/myfiles.tar.gz < myfiles.tar.gz
```

## SEE ALSO
podman(1), podman-mount(1), podman-umount(1)
**[podman(1)](podman.1.md)**, **[podman-mount(1)](podman-mount.1.md)**, **[podman-unmount(1)](podman-unmount.1.md)**

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