Assign to the variable x the new value f(x), making sure that no other thread may modify x between the read and the write.
require 'atomic'
x = Atomic.new(0) x.update { |x| f(x) }
(def x (atom 0)) (def f inc) (swap! x f)
#include <mutex>
//declaration auto mutex = std::mutex{}; auto x = someValue(); //use { auto lock = std::unique_lock{mutex}; x = f(x); }
#include <atomic>
std::atomic<int> x{}; auto local_x = x.load(); while(!x.compare_exchange_strong(local_x, f(local_x))) { local_x = x.load(); }
private readonly object m_Sync = new object(); lock(m_Sync) { x = f(x); }
lock (x) { x = f(x); }
synchronized x = f(x);
x = f(x);
x = f(x)
integer, dimension[*] :: x critical x = f(x) end critical
import "sync"
var lock sync.Mutex lock.Lock() x = f(x) lock.Unlock()
import Control.Concurrent.MVar
putMVar x . f =<< takeMVar x
let x = f(x)
synchronized(lock){ x = f(x); }
$mutex = Mutex::create(); Mutex::lock($mutex); $x = f($x); Mutex::unlock($mutex); Mutex::destroy($mutex);
uses syncobjs;
var loc: TCriticalSection; begin loc.Enter; try x := f(x); finally loc.Leave; end; end.
use threads; use threads::shared;
my $x :shared; $x = 0; sub my_task { my $id = shift; for (1 .. 5) { sleep 2*rand(); { # lock scope lock($x); print "thread $id found $x\n"; $x = $id; sleep 2*rand(); } } } threads->create('my_task', $_) for 1 .. 3; sleep 5 while threads->list(threads::running);
import threading
lock = threading.Lock() lock.acquire() try: x = f(x) finally: lock.release()
with threading.Lock(): x = f(x)
let mut x = x.lock().unwrap(); *x = f(x);
No security, no password. Other people might choose the same nickname.