// This wrapper uses syscall.Flock to prevent concurrent adb commands,
// so for now it only builds on platforms that support that system call.
// TODO(#33974): use a more portable library for file locking.

//go:build darwin || dragonfly || freebsd || illumos || linux || netbsd || openbsd

// This program can be used as go_android_GOARCH_exec by the Go tool.
// It executes binaries on an android device using adb.

	g()
}
</pre>

<p>
it can happen that <code>g</code> prints <code>2</code> and then <code>0</code>.
</p>

<p>
This fact invalidates a few common idioms.
</p>

<p>
Double-checked locking is an attempt to avoid the overhead of synchronization.
For example, the <code>twoprint</code> program might be
incorrectly written as:
</p>

<pre>
var a string
var done bool

func setup() {