PHP is developed and maintained by a global community of contributors.
The PHP Foundation helps fund this work. If PHP is part of your business or projects, consider sponsoring the Foundation.
下列常量由此扩展定义，且仅在此扩展编译入 PHP 或在运行时动态载入时可用。
MSG_IPC_NOWAIT
(int)
MSG_EAGAIN
(int)
MSG_ENOMSG
(int)
MSG_NOERROR
(int)
MSG_EXCEPT
(int)
