cp or mv files to same directory they are already in when I am in another?

Question

If I am in ~/blob and I have a file in ~/blob/a_long_directory_name/c/x.x

I can type

mv blob/a_long_directory_name/c/x.x blob/a_long_directory_name/even_more/y.y

Is there any shortcut whereby I can type something shorter that uses the directory path in the first param (not my current directory though), e.g.

mv blob/a_long_directory_name/c/x.x $same_dir/y.y

where something like $same_dir would point to the dir of param 1

Answer 1

With bash, you could use brace expansion

mv blob/a_long_directory_name/{c/x.x,evenmore/y.y}

Answer 2

To minimize the amount of typing, it's probably easiest to do it in two steps. CD to the directory, then move.

If you only have one command, you can use a subshell:

$ (cd blob/a_long_directory_name/c/ && mv x.x y.y )

That means the cd will only take effect in the subshell, the mv will only happen if the cd succeeds, and the working directory of your current shell won't change.

If you have more than one command, use the directory stack.

$ pushd blob/a_long_directory_name/c/
$ mv x.x y.y
$ mv z.z q.q
$ popd

Answer 3

You could use your shell's text substitution capabilities. In bash, you could use a beast like:

mv blob/a_long_directory_name/c/xx !#:$:gs^c/xx^evenmore/yy

To break it down:

!# is the current line typed so far

:$ asks to pick the last word (replace with a number n to pick n'th word) of the string under consideration (!# in this case). The last word of the line typed so far would be the previous word.

:gs^xx^yy does global (g) textual substitution (s) on the resulting word, replacing 'xx' with 'yy'. ^ is just a delimiter for the s command to allow using / in your patterns.

This method is slightly more general as it lets you replace any part of the path ('xx') with any other word ('yy').

Finally, like with any history manipulation, it's good to have appropriate shell options set (e.g. in ~/.bashrc). In this case

shopt -s histverify

will display the edited line after you press return, so you can still edit it and check for errors.

Why you'd use a construct like that I'm not sure, but it works in this case.