Why is it that Cygwin can run .bat scripts?

Question

When I execute a .bat script from bash in Cygwin, by what mechanism is it running? I understand that if I run a .EXE it will launch, regardless of whether the .EXE is from Cygwin or from a more traditional environment. I understand that when I execute an executable script with #! at the beginning that Cygwin supplies the magic for it to run.

But why does a .bat script work? Is there some component inside of Cygwin that is aware of what a Windows .bat script is and what to do with it? Or is it that it is somehow impossible under Windows to execute a call to launch a .EXE file that won't automatically also work for a .bat script instead?

Answer 1

I believe that bash in cygwin sees the bat extension as being flagged executable (a cygwin hit-tip to windows convention). As such it loads and executes the file with it's associated interpreter (cmd.exe, per os configuration), much as it creates a new instance of bash to run your #! scripts (per posix standard).