Example:
	//go:cgo_ldflag "-lpthread"
	//go:cgo_ldflag "-L/usr/local/sqlite3/lib"

A package compiled with cgo will include directives for both
internal and external linking; the linker will select the appropriate
subset for the chosen linking mode.

Example

As a simple example, consider a package that uses cgo to call C.sin.
The following code will be generated by cgo:

	// compiled by gc

pkg syscall (openbsd-386), const SYS_KILL = 37
pkg syscall (openbsd-386), const SYS_LSTAT = 293
pkg syscall (openbsd-386), const SYS_NANOSLEEP = 240
pkg syscall (openbsd-386), const SYS_SELECT = 93
pkg syscall (openbsd-386), const SYS_SETITIMER = 83
pkg syscall (openbsd-386), const SYS_SETTIMEOFDAY = 122
pkg syscall (openbsd-386), const SYS_STAT = 291
pkg syscall (openbsd-386), const SYS_STATFS = 307

</p>

<pre>
var limit = make(chan int, 3)

func main() {
	for _, w := range work {
		go func(w func()) {
			limit &lt;- 1
			w()
			&lt;-limit
		}(w)
	}
	select{}
}
</pre>

<h3 id="locks">Locks</h3>

<p>
The <code>sync</code> package implements two lock data types,
<code>sync.Mutex</code> and <code>sync.RWMutex</code>.
</p>

<p class="rule">