What's the difference between sh script and sh < script

Question

What's the difference between

sh myscript

and

sh < myscript

I played around and they seem to have the same effect. Are they equivalent?

Answer 1

They are not. There are some things that will not work. The one thing that comes to mind is:

sh myscript -flag1 -value=3

is not possible with sh < myscript.

With sh < myscript, $0 is set to sh, rather than myscript, so

echo this script is $0

won't work

Also, if your script reads input, it will not work - you cannot

sh < myscript < myfiletoread