.nh
.TH "DOCKER" "1" "Jan 2024" "Docker Community" "Docker User Manuals"

.SH NAME
.PP
docker-container-cp - Copy files/folders between a container and the local filesystem


.SH SYNOPSIS
.PP
\fBdocker container cp [OPTIONS] CONTAINER:SRC_PATH DEST_PATH|-
	docker cp [OPTIONS] SRC_PATH|- CONTAINER:DEST_PATH\fP


.SH DESCRIPTION
.PP
The \fBdocker container cp\fR utility copies the contents of \fBSRC_PATH\fR to the \fBDEST_PATH\fR\&.
You can copy from the container's file system to the local machine or the
reverse, from the local filesystem to the container. If \fB-\fR is specified for
either the \fBSRC_PATH\fR or \fBDEST_PATH\fR, you can also stream a tar archive from
\fBSTDIN\fR or to \fBSTDOUT\fR\&. The \fBCONTAINER\fR can be a running or stopped container.
The \fBSRC_PATH\fR or \fBDEST_PATH\fR can be a file or directory.

.PP
The \fBdocker container cp\fR command assumes container paths are relative to the container's
\fB/\fR (root) directory. This means supplying the initial forward slash is optional;
The command sees \fBcompassionate_darwin:/tmp/foo/myfile.txt\fR and
\fBcompassionate_darwin:tmp/foo/myfile.txt\fR 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 \fBdocker container cp\fR is
run.

.PP
The \fBcp\fR command behaves like the Unix \fBcp -a\fR 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 \fBUID:GID\fR of the root user. Files copied to the local
machine are created with the \fBUID:GID\fR of the user which invoked the \fBdocker container cp\fR
command.  If you specify the \fB-L\fR option, \fBdocker container cp\fR follows any symbolic link
in the \fBSRC_PATH\fR\&. \fBdocker container cp\fR does \fInot\fP create parent directories for
\fBDEST_PATH\fR if they do not exist.

.PP
Assuming a path separator of \fB/\fR, a first argument of \fBSRC_PATH\fR and second
argument of \fBDEST_PATH\fR, the behavior is as follows:

.RS
.IP \(bu 2
\fBSRC_PATH\fR specifies a file
.RS
.IP \(bu 2
\fBDEST_PATH\fR does not exist
.RS
.IP \(bu 2
the file is saved to a file created at \fBDEST_PATH\fR

.RE

.IP \(bu 2
\fBDEST_PATH\fR does not exist and ends with \fB/\fR
.RS
.IP \(bu 2
Error condition: the destination directory must exist.

.RE

.IP \(bu 2
\fBDEST_PATH\fR exists and is a file
.RS
.IP \(bu 2
the destination is overwritten with the source file's contents

.RE

.IP \(bu 2
\fBDEST_PATH\fR exists and is a directory
.RS
.IP \(bu 2
the file is copied into this directory using the basename from
\fBSRC_PATH\fR

.RE


.RE

.IP \(bu 2
\fBSRC_PATH\fR specifies a directory
.RS
.IP \(bu 2
\fBDEST_PATH\fR does not exist
.RS
.IP \(bu 2
\fBDEST_PATH\fR is created as a directory and the \fIcontents\fP of the source
directory are copied into this directory

.RE

.IP \(bu 2
\fBDEST_PATH\fR exists and is a file
.RS
.IP \(bu 2
Error condition: cannot copy a directory to a file

.RE

.IP \(bu 2
\fBDEST_PATH\fR exists and is a directory
.RS
.IP \(bu 2
\fBSRC_PATH\fR does not end with \fB/.\fR (that is: \fIslash\fP followed by \fIdot\fP)
.RS
.IP \(bu 2
the source directory is copied into this directory

.RE

.IP \(bu 2
\fBSRC_PATH\fR does end with \fB/.\fR (that is: \fIslash\fP followed by \fIdot\fP)
.RS
.IP \(bu 2
the \fIcontent\fP of the source directory is copied into this
directory

.RE


.RE


.RE


.RE

.PP
The command requires \fBSRC_PATH\fR and \fBDEST_PATH\fR to exist according to the above
rules. If \fBSRC_PATH\fR 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 \fB-L\fR option.

.PP
A colon (\fB:\fR) is used as a delimiter between \fBCONTAINER\fR and its path. You can
also use \fB:\fR when specifying paths to a \fBSRC_PATH\fR or \fBDEST_PATH\fR on a local
machine, for example  \fBfile:name.txt\fR\&. If you use a \fB:\fR in a local machine path,
you must be explicit with a relative or absolute path, for example:

.EX
`/path/to/file:name.txt` or `./file:name.txt`

.EE

.PP
It is not possible to copy certain system files such as resources under
\fB/proc\fR, \fB/sys\fR, \fB/dev\fR, tmpfs, and mounts created by the user in the container.
However, you can still copy such files by manually running \fBtar\fR in \fBdocker exec\fR\&.
For example (consider \fBSRC_PATH\fR and \fBDEST_PATH\fR are directories):

.EX
$ docker exec foo tar Ccf $(dirname SRC_PATH) - $(basename SRC_PATH) | tar Cxf DEST_PATH -

.EE

.PP
or

.EX
$ tar Ccf $(dirname SRC_PATH) - $(basename SRC_PATH) | docker exec -i foo tar Cxf DEST_PATH -

.EE

.PP
Using \fB-\fR as the \fBSRC_PATH\fR streams the contents of \fBSTDIN\fR as a tar archive.
The command extracts the content of the tar to the \fBDEST_PATH\fR in container's
filesystem. In this case, \fBDEST_PATH\fR must specify a directory. Using \fB-\fR as
the \fBDEST_PATH\fR streams the contents of the resource as a tar archive to \fBSTDOUT\fR\&.


.SH EXAMPLES
.PP
Suppose a container has finished producing some output as a file it saves
to somewhere in its filesystem. This could be the output of a build job or
some other computation. You can copy these outputs from the container to a
location on your local host.

.PP
If you want to copy the \fB/tmp/foo\fR directory from a container to the
existing \fB/tmp\fR directory on your host. If you run \fBdocker container cp\fR in your \fB~\fR
(home) directory on the local host:

.EX
$ docker container cp compassionate_darwin:tmp/foo /tmp

.EE

.PP
Docker creates a \fB/tmp/foo\fR directory on your host. Alternatively, you can omit
the leading slash in the command. If you execute this command from your home
directory:

.EX
$ docker container cp compassionate_darwin:tmp/foo tmp

.EE

.PP
If \fB~/tmp\fR does not exist, Docker will create it and copy the contents of
\fB/tmp/foo\fR from the container into this new directory. If \fB~/tmp\fR already
exists as a directory, then Docker will copy the contents of \fB/tmp/foo\fR from
the container into a directory at \fB~/tmp/foo\fR\&.

.PP
When copying a single file to an existing \fBLOCALPATH\fR, the \fBdocker container cp\fR command
will either overwrite the contents of \fBLOCALPATH\fR if it is a file or place it
into \fBLOCALPATH\fR if it is a directory, overwriting an existing file of the same
name if one exists. For example, this command:

.EX
$ docker container cp sharp_ptolemy:/tmp/foo/myfile.txt /test

.EE

.PP
If \fB/test\fR does not exist on the local machine, it will be created as a file
with the contents of \fB/tmp/foo/myfile.txt\fR from the container. If \fB/test\fR
exists as a file, it will be overwritten. Lastly, if \fB/test\fR exists as a
directory, the file will be copied to \fB/test/myfile.txt\fR\&.

.PP
Next, suppose you want to copy a file or folder into a container. For example,
this could be a configuration file or some other input to a long running
computation that you would like to place into a created container before it
starts. This is useful because it does not require the configuration file or
other input to exist in the container image.

.PP
If you have a file, \fBconfig.yml\fR, in the current directory on your local host
and wish to copy it to an existing directory at \fB/etc/my-app.d\fR in a container,
this command can be used:

.EX
$ docker container cp config.yml myappcontainer:/etc/my-app.d

.EE

.PP
If you have several files in a local directory \fB/config\fR which you need to copy
to a directory \fB/etc/my-app.d\fR in a container:

.EX
$ docker container cp /config/. myappcontainer:/etc/my-app.d

.EE

.PP
The above command will copy the contents of the local \fB/config\fR directory into
the directory \fB/etc/my-app.d\fR in the container.

.PP
Finally, if you want to copy a symbolic link into a container, you typically
want to  copy the linked target and not the link itself. To copy the target, use
the \fB-L\fR option, for example:

.EX
$ ln -s /tmp/somefile /tmp/somefile.ln
$ docker container cp -L /tmp/somefile.ln myappcontainer:/tmp/

.EE

.PP
This command copies content of the local \fB/tmp/somefile\fR into the file
\fB/tmp/somefile.ln\fR in the container. Without \fB-L\fR option, the \fB/tmp/somefile.ln\fR
preserves its symbolic link but not its content.


.SH OPTIONS
.PP
\fB-a\fP, \fB--archive\fP[=false]
	Archive mode (copy all uid/gid information)

.PP
\fB-L\fP, \fB--follow-link\fP[=false]
	Always follow symbol link in SRC_PATH

.PP
\fB-h\fP, \fB--help\fP[=false]
	help for cp


.SH SEE ALSO
.PP
\fBdocker-container(1)\fP