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copied!<p>Since you are making a distributed lock service, I assume your lock server listens on a port, and when you accept() a connection you loop, waiting for commands in a goroutine per connection. And that goroutine exits when the socket is dropped (ie: remote node crash)</p> <p>So, assuming that is true, you can do a couple things.</p> <p>1) create a channel with a depth matching how many concurrent locks 2) when you lock, send a message to the channel (it will block if full) 3) when you unlock, just read a message from the channel 4) you can "defer release()" (where release consumes a message if you have already locked)</p> <p>Here's a rough working example, all but the socket stuff. Hopefully it makes sense. <a href="http://play.golang.org/p/DLOX7m8m6q" rel="nofollow">http://play.golang.org/p/DLOX7m8m6q</a></p> <pre><code>package main import "fmt" import "time" type Locker struct { ch chan int locked bool } func (l *Locker) lock(){ l.ch <- 1 l.locked=true } func (l *Locker) unlock() { if l.locked { // called directly or via defer, make sure we don't unlock if we don't have the lock l.locked = false // avoid unlocking twice if socket crashes after unlock <- l.ch } } func dostuff(name string, locker Locker) { locker.lock() defer locker.unlock() fmt.Println(name,"Doing stuff") time.Sleep(1 * time.Second) } func main() { ch := make(chan int, 2) go dostuff("1",Locker{ch,false}) go dostuff("2",Locker{ch,false}) go dostuff("3",Locker{ch,false}) go dostuff("4",Locker{ch,false}) time.Sleep(4 * time.Second) } </code></pre>

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