--- 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`.