Running php functions after eachother [duplicate] - php

Question

This question already has answers here:
Synchronized functions in PHP
(6 answers)
Closed 9 years ago.
I've got a php application that requires to make a connection to a server which authenticates with a token, this token stays valid until connection is lost.
When another connection is made while the first is still open my application crashes because the token is different from the currently connected one...
public function connect()
{
$Socket = fsockopen("192.168.1.1", 1234);
if ($Socket !== false) {
stream_set_timeout($Socket, static::TIMEOUT_SEC, static::TIMEOUT_USEC);
$this->socket = $Socket;
$this->sendeverything;
}
}
How am I able to run a function like:
function gogogo() {
connect();
}
multiple times without having them running simultaneously
Sorry for my bad english

Answer 1

Most easy solution would be to have a is_connected function:
function connect() {
if(is_already_connected()) {
return;
}
// ... your connect logic
}
In the is_already_connected() you'll have to write some intelligent code to determine if there is an open connection.
You can also create a kind of singleton connection (although this suggestion would probably instantiate a lot of debate about the use of singletons ;))

Answer 2

Try something like this...
<?php
class Connection {
public $Socket = null;
public function connect(){
// Checking if Socket already has a pointer :P
if((bool)$this->Socket){
return true;
}
$this->Socket = fsockopen("192.168.1.1", 1234);
if ($this->Socket !== false) {
stream_set_timeout($this->Socket, static::TIMEOUT_SEC, static::TIMEOUT_USEC);
$this->sendeverything();
}
}
}
$myconnect = new Connection();
$myconnect->connect();
$myconnect->connect();
?>

Answer 3

As mentioned in this question you can use sem_aquire for this. Something like:
function connect(){
$key = "192.168.1.1:1234" ;
try{
$sem = sem_get( $SEMKey);
sem_acquire($sem);
//Do connecty stuff here
sem_release($sem);
}catch(Exception $ex){
//Exception handling
}finally{
//Finally only available in PHP 5.5 place this in catch and try if < 5.5
sem_release($sem);
}
}
Note that this is entirely untested and wont work on windows. If you are on windows you can use flock - again as mentioned in the above question.