file to blob

Hi, I am relatively new to php and could use a good pointing in the right direction. I have a soap client in NuSoap that I developed for a webservice that I wrote in another language and I need it to be able to send a file in a blob. I can't find an example of how you load a file in its entirety (not just the content) into a blob in PHP. I need to be able to do this because the webservice that is being called recreates the document locally for the user. Can this be done in PHP? Thanks Joshua