You have to save the PDF as that's the only way FileMaker can generate the PDF for attachment to an email. The location to which it is saved, however, can be the temporary items folder on the users computer.
Here's a link to a thread where I described something very similar to this: Found Sets to PDF with unique file names
Just use Get ( TemporaryPath ) in place of Get ( DesktopPath )
Thanks Phil. I will try that, but how do I get the email to automatically attach the file as necessary?
In your send mail script step, click the check box for an attachment and enter the path variable used to compute the path and file name for the Save as PDF step.