Is there a function that reads the entire contents of a std.stdio.File?

[Jay via Digitalmars-d-learn]

all the functions/methods i've come across so far deal with 
either streams or just file names (like std.file.read) and there 
doesn't seem to be a way to wrap a std.stdio.File in a stream (or 
is there?). i need a function that takes a std.stdio.File and 
returns a string or byte array.