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

[Jay via Digitalmars-d-learn]

On Tuesday, 16 September 2014 at 14:49:08 UTC, Daniel Kozak via 
Digitalmars-d-learn wrote:
> You can use rawRead:
> http://dlang.org/phobos/std_stdio.html#.File.rawRead

for that i need to know the size of the contents. is there a 
function that does that for me? i'm looking for something like 
someFile.readAll(). and it shouldn't matter whether the File 
instance represents a regular file or a pipe/stream.