PHP socket_addrinfo_connect() Function: Usage and Examples

Connects a socket using an address-info object. This guide demonstrates its use in PHP code and explains when the result or side effect needs extra checks.

What It Does

Connects a socket using an address-info object.

Syntax and Parameters

The examples below show a real call to socket_addrinfo_connect with suitable arguments. Read the function call in context: its connection, handle, input data or other prerequisites are created before use.

Requirements: Sockets extension; operating-system networking support.

These examples are for an isolated development environment. Hostnames, credentials and remote paths must be replaced with your approved configuration.

Example 1: Core Behavior

Use local loopback or a connected socket pair to avoid unintended public network exposure.

<?php
$listener = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
socket_bind($listener, "127.0.0.1", 0);
socket_getsockname($listener, $ip, $port);
socket_listen($listener, 1);
$addresses = socket_addrinfo_lookup($ip, (string) $port, ["ai_family" => AF_INET, "ai_socktype" => SOCK_STREAM]);
$address = $addresses[0];
$result = socket_addrinfo_connect($address);
echo is_object($result) ? get_debug_type($result) : (is_array($result) ? json_encode($result) : var_export($result, true));
if ($result instanceof Socket) socket_close($result);
socket_close($listener);

Observe the returned value or changed resource state. A successful function call can still require additional checks before a higher-level operation is considered successful.

Example 2: Alternative or Failure Case

The operation may return a status or a partial byte count depending on timing and transport.

<?php
$listener = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
socket_bind($listener, "127.0.0.1", 0);
socket_getsockname($listener, $ip, $port);
socket_listen($listener, 1);
$addresses = socket_addrinfo_lookup($ip, (string) $port, ["ai_family" => AF_INET, "ai_socktype" => SOCK_STREAM]);
$address = $addresses[0];
$result = socket_addrinfo_connect($address);
echo is_object($result) ? get_debug_type($result) : (is_array($result) ? json_encode($result) : var_export($result, true));
if ($result instanceof Socket) { socket_getpeername($result, $ip, $port); echo "Peer: $ip:$port"; socket_close($result); }
socket_close($listener);

Compare the different inputs, environment assumptions or result checks. Do not use a transport-level success value as proof that all business-level requirements were met.

Practical Example: Applying the Rule

Apply explicit timeouts and check errors before integrating the code into a long-running server.

<?php
$listener = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
socket_bind($listener, "127.0.0.1", 0);
socket_getsockname($listener, $ip, $port);
socket_listen($listener, 1);
$addresses = socket_addrinfo_lookup($ip, (string) $port, ["ai_family" => AF_INET, "ai_socktype" => SOCK_STREAM]);
$address = $addresses[0];
$result = socket_addrinfo_connect($address);
echo is_object($result) ? get_debug_type($result) : (is_array($result) ? json_encode($result) : var_export($result, true));
if ($result instanceof Socket) { socket_send($result, "hello", 5, 0); $accepted = socket_accept($listener); if ($accepted) { $buf = ""; socket_recv($accepted, $buf, 16, 0); echo "Received: " . $buf; socket_close($accepted); } socket_close($result); }
socket_close($listener);

In an application, convert low-level failures into controlled responses and log only non-sensitive diagnostic context.

Important Behavior and Edge Cases

Do not use address lookup results from arbitrary URLs without validating destination ranges.

Network operations can block or read/write only part of a message. Treat end-of-stream, timeout and transient errors separately.

Comparison with Related Functions or Patterns

Common Beginner Mistakes

Key Takeaways

• Connects a socket using an address-info object.
• Do not use address lookup results from arbitrary URLs without validating destination ranges.
• socket_connect connects an existing socket to a specified address.

Select this API or pattern based on its documented behavior and the trust boundaries in your own application, and test all external integrations against their actual deployments.