mirror of https://github.com/docker/cli.git
132 lines
5.4 KiB
Markdown
132 lines
5.4 KiB
Markdown
---
|
|
title: "cp"
|
|
description: "The cp command description and usage"
|
|
keywords: "copy, container, files, folders"
|
|
---
|
|
|
|
# cp
|
|
|
|
```markdown
|
|
Usage: docker cp [OPTIONS] CONTAINER:SRC_PATH DEST_PATH|-
|
|
docker cp [OPTIONS] SRC_PATH|- CONTAINER:DEST_PATH
|
|
|
|
Copy files/folders between a container and the local filesystem
|
|
|
|
Use '-' as the source to read a tar archive from stdin
|
|
and extract it to a directory destination in a container.
|
|
Use '-' as the destination to stream a tar archive of a
|
|
container source to stdout.
|
|
|
|
Options:
|
|
-L, --follow-link Always follow symbol link in SRC_PATH
|
|
-a, --archive Archive mode (copy all uid/gid information)
|
|
--help Print usage
|
|
```
|
|
|
|
## Description
|
|
|
|
The `docker cp` utility copies the contents of `SRC_PATH` to the `DEST_PATH`.
|
|
You can copy from the container's file system to the local machine or the
|
|
reverse, from the local filesystem to the container. If `-` is specified for
|
|
either the `SRC_PATH` or `DEST_PATH`, you can also stream a tar archive from
|
|
`STDIN` or to `STDOUT`. The `CONTAINER` can be a running or stopped container.
|
|
The `SRC_PATH` or `DEST_PATH` can be a file or directory.
|
|
|
|
The `docker cp` command assumes container paths are relative to the container's
|
|
`/` (root) directory. 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. 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 `docker cp` is
|
|
run.
|
|
|
|
The `cp` command behaves like the Unix `cp -a` command in that directories are
|
|
copied recursively with permissions preserved if possible. Ownership is set to
|
|
the user and primary group at the destination. For example, files copied to a
|
|
container are created with `UID:GID` of the root user. Files copied to the local
|
|
machine are created with the `UID:GID` of the user which invoked the `docker cp`
|
|
command. However, if you specify the `-a` option, `docker cp` sets the ownership
|
|
to the user and primary group at the source.
|
|
If you specify the `-L` option, `docker cp` follows any symbolic link
|
|
in the `SRC_PATH`. `docker cp` does *not* create parent directories for
|
|
`DEST_PATH` if they do not exist.
|
|
|
|
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
|
|
- `DEST_PATH` does not exist
|
|
- the file is saved to a file created at `DEST_PATH`
|
|
- `DEST_PATH` does not exist and ends with `/`
|
|
- Error condition: the destination directory must exist.
|
|
- `DEST_PATH` exists and is a file
|
|
- 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 basename from
|
|
`SRC_PATH`
|
|
- `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` exists and is a file
|
|
- Error condition: cannot copy a directory to a file
|
|
- `DEST_PATH` exists and is a directory
|
|
- `SRC_PATH` does not end with `/.` (that is: _slash_ followed by _dot_)
|
|
- the source directory is copied into this directory
|
|
- `SRC_PATH` does end with `/.` (that is: _slash_ followed by _dot_)
|
|
- 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 link, not
|
|
the target, is copied by default. To copy the link target and not the link, specify
|
|
the `-L` option.
|
|
|
|
A colon (`:`) is used as a delimiter between `CONTAINER` and its path. You can
|
|
also use `:` when specifying paths to a `SRC_PATH` or `DEST_PATH` on a local
|
|
machine, for example `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`
|
|
|
|
## Examples
|
|
|
|
Copy a local file into container
|
|
|
|
```console
|
|
$ docker cp ./some_file CONTAINER:/work
|
|
```
|
|
|
|
Copy files from container to local path
|
|
|
|
```console
|
|
$ docker cp CONTAINER:/var/logs/ /tmp/app_logs
|
|
```
|
|
|
|
Copy a file from container to stdout. Please note `cp` command produces a tar stream
|
|
|
|
```console
|
|
$ docker cp CONTAINER:/var/logs/app.log - | tar x -O | grep "ERROR"
|
|
```
|
|
|
|
### Corner cases
|
|
|
|
It is not possible to copy certain system files such as resources under
|
|
`/proc`, `/sys`, `/dev`, [tmpfs](run.md#tmpfs), and mounts created by
|
|
the user in the container. However, you can still copy such files by manually
|
|
running `tar` in `docker exec`. Both of the following examples do the same thing
|
|
in different ways (consider `SRC_PATH` and `DEST_PATH` are directories):
|
|
|
|
```console
|
|
$ docker exec CONTAINER tar Ccf $(dirname SRC_PATH) - $(basename SRC_PATH) | tar Cxf DEST_PATH -
|
|
```
|
|
|
|
```console
|
|
$ tar Ccf $(dirname SRC_PATH) - $(basename SRC_PATH) | docker exec -i CONTAINER tar Cxf DEST_PATH -
|
|
```
|
|
|
|
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 container's
|
|
filesystem. In this case, `DEST_PATH` must specify a directory. Using `-` as
|
|
the `DEST_PATH` streams the contents of the resource as a tar archive to `STDOUT`.
|