connection_status() function in PHP

The connection_status() function in PHP returns the status of the current connection between the server and client. This function is particularly useful for checking if a user has disconnected from a long-running script.

Syntax

connection_status()

Parameters

This function does not accept any parameters.

Return Value

The connection_status() function returns an integer representing the connection status bitfield −

• 0 - CONNECTION_NORMAL - connection is running normally

• 1 - CONNECTION_ABORTED - connection is aborted by user or network error

• 2 - CONNECTION_TIMEOUT - connection timed out

• 3 - CONNECTION_ABORTED & CONNECTION_TIMEOUT - both conditions occurred

Example

The following example demonstrates how to check the connection status and display appropriate messages −

<?php
    switch (connection_status()) {
        case CONNECTION_NORMAL:
            $msg = 'Connection is in a normal state!';
            break;
        case CONNECTION_ABORTED:
            $msg = 'Connection aborted!';
            break;
        case CONNECTION_TIMEOUT:
            $msg = 'Connection timed out!';
            break;
        case (CONNECTION_ABORTED & CONNECTION_TIMEOUT):
            $msg = 'Connection aborted and timed out!';
            break;
        default:
            $msg = 'Status is unknown!';
            break;
    }
    echo $msg;
?>

Connection is in a normal state!

Practical Use Case

This function is commonly used in long-running scripts to check if the client is still connected −

<?php
    for ($i = 1; $i <= 100; $i++) {
        if (connection_status() != CONNECTION_NORMAL) {
            error_log("Client disconnected at iteration $i");
            break;
        }
        
        // Simulate long-running task
        sleep(1);
        echo "Processing step $i...<br>";
        flush();
    }
?>

Conclusion

The connection_status() function is essential for monitoring client connections in long-running PHP scripts. It helps prevent unnecessary processing when clients disconnect and enables proper resource cleanup.