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.

2009-02-18 20:35:47

What Others Think

Very cool. I'm pretty sure that the comma is not expanded: it's the empty string that it delimits.
zabouti · 667 weeks and 3 days ago
Why is there some time sound is not working in window 10 PC no sound in windows 10 how to fix sound problems in windows 10.
KGF123 · 59 weeks and 6 days ago
These strings work differently when you run them within the program and it's hard to handle them. I pick some codes from which I am going to combine with them.
Connor2323 · 32 weeks and 4 days ago
seofox · 2 weeks and 2 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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