In many Books and on many Sites I see -drain. Well, for an Autorelease Pool that sounds cool. But does it do anything other than an release? I would guess -drain just makes the Pool to -release all it's objects, without releasing the Pool itself. Just a guess.
Source: Tips4all
Note that the comments on oxigen's answer saying that -drain does not release the NSAutoreleasePool are not correct. The documentation for NSAutoreleasePool clearly says that -drain releases (and thus destroys) the NSAutoreleasePool.
ReplyDelete-drain is a replacement for using -release for NSAutoreleasePool objects, the only difference being that provides a hint to the garbage collection system.
Oxigen is right, see the documentation for method drain of NSAutoreleasePool:
ReplyDeleteIn a reference-counted environment,
releases and pops the receiver; in a
garbage-collected environment,
triggers garbage collection if the
memory allocated since the last
collection is greater than the current
threshold.
If your system has a garbage Collection, then -drain send message (objc_collect_if_needed) for GC
ReplyDeleteIf you haven't GC, then drain = release