Bash: manipulating with strings (percent sign)

Question

What does a percent sign mean in bash when manipulating strings? For example, what does ${0%/*} mean?

Answer 1

If you use @fedorqui's resource, you'll see it is going to strip the shortest match of /* from the end of the first positional argument. An example:

example_foo(){
    echo ${1%/*}
}

example_foo path/to/directory/sub_directory
# => path/to/directory

In the example I used the second positional argument since the first is the name of the function.