Can I send a file (or long bit stream) as a command argument?

Hi,

Suppose I wanted to send a 4K binary file, is this possible as an argument to a command?
Will I run across any limitations in buffering or potentially stability of the serial line?

Or, perhaps I could send a command to start receiving the stream; and then another command to such as <EOF>.
I'm guessing I'd have to ASCII encode the bytes or something.

Thanks!

-John