Linux: copy and create destination dir if it does not exist

mkdir -p "$d" && cp file "$d"

(there's no such option for cp).

If both of the following are true:

1. You are using the GNU version of cp (and not, for instance, the Mac version), and
2. You are copying from some existing directory structure and you just need it recreated

then you can do this with the --parents flag of cp. From the info page (viewable at http://www.gnu.org/software/coreutils/manual/html_node/cp-invocation.html#cp-invocation or with info cp or man cp):

--parents     Form the name of each destination file by appending to the target     directory a slash and the specified name of the source file.  The     last argument given to `cp' must be the name of an existing     directory.  For example, the command:          cp --parents a/b/c existing_dir     copies the file `a/b/c' to `existing_dir/a/b/c', creating any     missing intermediate directories.

Example:

/tmp $ mkdir foo/tmp $ mkdir foo/foo/tmp $ touch foo/foo/foo.txt/tmp $ mkdir bar/tmp $ cp --parents foo/foo/foo.txt bar/tmp $ ls bar/foo/foofoo.txt

Short Answer

To copy myfile.txt to /foo/bar/myfile.txt, use:

mkdir -p /foo/bar && cp myfile.txt $_

How does this work?

There's a few components to this, so I'll cover all the syntax step by step.

The mkdir utility, as specified in the POSIX standard, makes directories. The -p argument, per the docs, will cause mkdir to

Create any missing intermediate pathname components

meaning that when calling mkdir -p /foo/bar, mkdir will create /foo and /foo/bar if /foo doesn't already exist. (Without -p, it will instead throw an error.

The && list operator, as documented in the POSIX standard (or the Bash manual if you prefer), has the effect that cp myfile.txt $_ only gets executed if mkdir -p /foo/bar executes successfully. This means the cp command won't try to execute if mkdir fails for one of the many reasons it might fail.

Finally, the $_ we pass as the second argument to cp is a "special parameter" which can be handy for avoiding repeating long arguments (like file paths) without having to store them in a variable. Per the Bash manual, it:

expands to the last argument to the previous command

In this case, that's the /foo/bar we passed to mkdir. So the cp command expands to cp myfile.txt /foo/bar, which copies myfile.txt into the newly created /foo/bar directory.

Note that $_ is not part of the POSIX standard, so theoretically a Unix variant might have a shell that doesn't support this construct. However, I don't know of any modern shells that don't support $_; certainly Bash, Dash, and zsh all do.

A final note: the command I've given at the start of this answer assumes that your directory names don't have spaces in. If you're dealing with names with spaces, you'll need to quote them so that the different words aren't treated as different arguments to mkdir or cp. So your command would actually look like:

mkdir -p "/my directory/name with/spaces" && cp "my filename with spaces.txt" "$_"