Increments the receiver�s reference count.
Original signature is '- (id)retain'
Available in Mac OS X v10.0 and later.
[Missing <returns> documentation for "M:Monobjc.Id.Retain"]
- Available in Monobjc Bridge: 10.6 (For Mac OS X 10.6 and later), 10.5 (For Mac OS X 10.5 and later)