bash shell expansion

cp /really/long/path/and/file/name{,-`date -I`}
The expansion {,} in bash will repeat the given string once for each item seperated by commas. The given command will result in the following being run: cp /really/long/path/and/file/name /really/long/path/and/file/name-`date -I` These can be embedded as needed, ex: rm file{1,2,3{1,2,3}} would delete the files file1, file2, file31, file32, file32, and no other files.

4
2009-02-18 20:35:47
cp

What Others Think

Very cool. I'm pretty sure that the comma is not expanded: it's the empty string that it delimits.
zabouti · 500 weeks and 4 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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