When I typed perl and the file name the first time nothing happened. The second time i did it (right below the first time in the cmd window) it told me my code had errors (no surprise). So... the second time it ran obviously. It is a very weird problem I know. Even the teacher couldn't figure it out.
Re: cmd window stays on my screen but I have to drag it into the window several times to get it to run.
You must be a Mac user? This is a unique feature on the windows version of Perl. In the windows version you can have the folder open were the .pl file is and the cmd window open and drag the file from the it's location into the cmd window, press enter and have it execute it.