Xcode 3.2 provides an awesome new feature under the Build menu, "Build and Archive" which generates an .ipa file suitable for Ad Hoc distribution. You can also open the Organizer, go to "Archived Applications," and "Submit Application to iTunesConnect."
Is there a way to use "Build and Archive" from the command line (as part of a build script)? I'd assume that xcodebuild would be involved somehow, but the man page doesn't seem to say anything about this.
UPDATE Michael Grinich requested clarification; here's what exactly you can't do with command-line builds, features you can ONLY do with Xcode's Organizer after you "Build and Archive."
You can click "Share Application..." to share your IPA with beta testers. As Guillaume points out below, due to some Xcode magic, this IPA file does not require a separately distributed .mobileprovision file that beta testers need to install; that's magical. No command-line script can do it. For example, Arrix's script (submitted May 1) does not meet that requirement.
More importantly, after you've beta tested a build, you can click "Submit Application to iTunes Connect" to submit that EXACT same build to Apple, the very binary you tested, without rebuilding it. That's impossible from the command line, because signing the app is part of the build process; you can sign bits for Ad Hoc beta testing OR you can sign them for submission to the App Store, but not both. No IPA built on the command-line can be beta tested on phones and then submitted directly to Apple.
I'd love for someone to come along and prove me wrong: both of these features work great in the Xcode GUI and cannot be replicated from the command line.
