How do I find all files that do not begin with a given prefix in bash?

Question

I have a bunch of files in a folder:

foo_1 
foo_2
foo_3
bar_1
bar_2
buzz_1
...

I want to find all the files that do not st

Answer 1

With extended globs:

shopt -s extglob
ls !(bar_*) > filelist.txt

The !(pattern) matches anything but pattern, so !(bar_*) is any filename that does not start with bar_.