must be a combination of MSG_OOB, MSG_PEEK, MSG_WAITALL, MSG_DONTWAIT, MSG_ERRQUEUE, and MSG_CMSG_CLOEXEC for AF_PACKET sockets

Description

PHP 8.6 adds raw AF_PACKET support to socket_recvfrom(). On a packet socket, only a finite subset of MSG_* flags is safe to use for receiving: MSG_OOB, MSG_PEEK, MSG_WAITALL, MSG_DONTWAIT, MSG_ERRQUEUE, and MSG_CMSG_CLOEXEC. Notably, MSG_TRUNC is excluded, since on a packet socket it makes recvfrom() report the untruncated frame length, which can exceed the supplied buffer.

Passing any flag outside this set on an AF_PACKET socket throws a ValueError, instead of risking a buffer-size mismatch.

Example

<?php

$socket = socket_create(AF_PACKET, SOCK_RAW, 0);

socket_recvfrom($socket, $data, 2048, MSG_TRUNC, $address, $port);

?>

Literal Examples

socket_recvfrom(): Argument #4 ($flags) must be a combination of MSG_OOB, MSG_PEEK, MSG_WAITALL, MSG_DONTWAIT, MSG_ERRQUEUE, and MSG_CMSG_CLOEXEC for AF_PACKET sockets

Alternatives

When calling socket_recvfrom() on an AF_PACKET socket, only combine flags from MSG_OOB, MSG_PEEK, MSG_WAITALL, MSG_DONTWAIT, MSG_ERRQUEUE, and MSG_CMSG_CLOEXEC.

Changed Behavior

This error may appear following an evolution in behavior, in previous versions. See

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