How can I get the current date in YYYY-MM-DD format in (OS X) bash?

Writing a shell script and I want to do something like this:

cp myfile.ext myfile.2011-06-10.ext

where 2011-06-10 is the current date.

Thoughts?

cp myfile.ext myfile.`date +%Y-%m-%d`.ext

or use shorthand format

date +%F

Try

 cp myfile.ext myfile.`date "+%Y-%m-%d"`.ext

and for a proper solution, decompose the name first into basename and extension, assign the date and then reassemble for final targetname.

The key is that

 date +FORMAT

allows for very rich format strings. See date --help or the rather fine manual.

The man page for the date utility contains examples of how to output the date in various ways.

cp myfile.ext myfile.$(date +%F).ext