Predefined Constants

The constants below are defined by this extension, and will only be available when the extension has either been compiled into PHP or dynamically loaded at runtime.

AF_UNIX (integer)

AF_INET (integer)

AF_INET6 (integer)

Only available if compiled with IPv6 support.

SOCK_STREAM (integer)

SOCK_DGRAM (integer)

SOCK_RAW (integer)

SOCK_SEQPACKET (integer)

SOCK_RDM (integer)

MSG_OOB (integer)

MSG_WAITALL (integer)

MSG_PEEK (integer)

MSG_DONTROUTE (integer)

MSG_EOR (integer)

Not available on Windows platforms.

MSG_EOF (integer)

Not available on Windows platforms.

SO_DEBUG (integer)

SO_REUSEADDR (integer)

SO_REUSEPORT (integer)

This constant is only available in PHP 5.4.10 or later on platforms that support the SO_REUSEPORT socket option: this includes macOS and FreeBSD, but does not include Linux or Windows.

SO_KEEPALIVE (integer)

SO_DONTROUTE (integer)

SO_LINGER (integer)

SO_BROADCAST (integer)

SO_OOBINLINE (integer)

SO_SNDBUF (integer)

SO_RCVBUF (integer)

SO_SNDLOWAT (integer)

SO_RCVLOWAT (integer)

SO_SNDTIMEO (integer)

SO_RCVTIMEO (integer)

SO_TYPE (integer)

SO_ERROR (integer)

TCP_NODELAY (integer)

Used to disable Nagle TCP algorithm. Added in PHP 5.2.7.

SOL_SOCKET (integer)

PHP_NORMAL_READ (integer)

PHP_BINARY_READ (integer)

SOL_TCP (integer)

SOL_UDP (integer)

The following constants are defined under Windows and UNIX-like platforms. Each constant is only defined if their equal is available on the platform.

SOCKET_EINTR (integer)

Interrupted system call.

SOCKET_EBADF (integer)

Bad file number.

SOCKET_EACCES (integer)

Permission denied.

SOCKET_EFAULT (integer)

Bad address.

SOCKET_EINVAL (integer)

Invalid argument.

SOCKET_EMFILE (integer)

Too many open files.

SOCKET_ENAMETOOLONG (integer)

File name too long.

SOCKET_ENOTEMPTY (integer)

Directory not empty.

SOCKET_ELOOP (integer)

Too many symbolic links encountered.

SOCKET_EWOULDBLOCK (integer)

Operation would block.

SOCKET_EREMOTE (integer)

Object is remote.

SOCKET_EUSERS (integer)

Too many users.

SOCKET_ENOTSOCK (integer)

Socket operation on non-socket.

SOCKET_EDESTADDRREQ (integer)

Destination address required.

SOCKET_EMSGSIZE (integer)

Message too long.

SOCKET_EPROTOTYPE (integer)

Protocol wrong type for socket.

SOCKET_EPROTONOSUPPORT (integer)

Protocol not supported.

SOCKET_ESOCKTNOSUPPORT (integer)

Socket type not supported.

SOCKET_EOPNOTSUPP (integer)

Operation not supported on transport endpoint.

SOCKET_EPFNOSUPPORT (integer)

Protocol family not supported.

SOCKET_EAFNOSUPPORT (integer)

Address family not supported by protocol.

SOCKET_EADDRNOTAVAIL (integer)

Cannot assign requested address.

SOCKET_ENETDOWN (integer)

Network is down.

SOCKET_ENETUNREACH (integer)

Network is unreachable.

SOCKET_ENETRESET (integer)

Network dropped connection because of reset.

SOCKET_ECONNABORTED (integer)

Software caused connection abort.

SOCKET_ECONNRESET (integer)

Connection reset by peer.

SOCKET_ENOBUFS (integer)

No buffer space available.

SOCKET_EISCONN (integer)

Transport endpoint is already connected.

SOCKET_ENOTCONN (integer)

Transport endpoint is not connected.

SOCKET_ESHUTDOWN (integer)

Cannot send after transport endpoint shutdown.

SOCKET_ETIMEDOUT (integer)

Connection timed out.

SOCKET_ECONNREFUSED (integer)

Connection refused.

SOCKET_EHOSTDOWN (integer)

Host is down.

SOCKET_EHOSTUNREACH (integer)

No route to host.

SOCKET_EALREADY (integer)

Operation already in progress.

SOCKET_EINPROGRESS (integer)

Operation now in progress.

The following constants are only defined under Windows.

SOCKET_ENOPROTOOPT (integer)

SOCKET_EADDRINUSE (integer)

SOCKET_ETOOMYREFS (integer)

SOCKET_EPROCLIM (integer)

SOCKET_EDUOT (integer)

SOCKET_ESTALE (integer)

SOCKET_EDISCON (integer)

SOCKET_SYSNOTREADY (integer)

SOCKET_VERNOTSUPPORTED (integer)

SOCKET_NOTINITIALISED (integer)

SOCKET_HOST_NOT_FOUND (integer)

SOCKET_TRY_AGAIN (integer)

SOCKET_NO_RECOVERY (integer)

SOCKET_NO_DATA (integer)

SOCKET_NO_ADDRESS (integer)

The following constants are only available on UNIX-like platforms. Each constant is only defined if their equal is available on the platform.

SOCKET_EPERM (integer)

Operation not permitted.

SOCKET_ENOENT (integer)

No such file or directory.

SOCKET_EIO (integer)

I/O error.

SOCKET_ENXIO (integer)

No such device or address.

SOCKET_E2BIG (integer)

Arg list too long.

SOCKET_EAGAIN (integer)

Try again.

SOCKET_ENOMEM (integer)

Out of memory.

SOCKET_ENOTBLK (integer)

Block device required.

SOCKET_EBUSY (integer)

Device or resource busy.

SOCKET_EEXIST (integer)

File exists.

SOCKET_EXDEV (integer)

Cross-device link.

SOCKET_ENODEV (integer)

No such device.

SOCKET_ENOTDIR (integer)

Not a directory.

SOCKET_EISDIR (integer)

Is a directory.

SOCKET_ENFILE (integer)

File table overflow.

SOCKET_ENOTTY (integer)

Not a typewriter.

SOCKET_ENOSPC (integer)

No space left on device.

SOCKET_ESPIPE (integer)

Illegal seek.

SOCKET_EROFS (integer)

Read-only file system.

SOCKET_EMLINK (integer)

Too many links.

SOCKET_EPIPE (integer)

Broken pipe.

SOCKET_ENOLCK (integer)

No record locks available.

SOCKET_ENOSYS (integer)

Function not implemented.

SOCKET_ENOMSG (integer)

No message of desired type.

SOCKET_EIDRM (integer)

Identifier removed.

SOCKET_ECHRNG (integer)

Channel number out of range.

SOCKET_EL2NSYNC (integer)

Level 2 not synchronized.

SOCKET_EL3HLT (integer)

Level 3 halted.

SOCKET_EL3RST (integer)

Level 3 reset.

SOCKET_ELNRNG (integer)

Link number out of range.

SOCKET_EUNATCH (integer)

Protocol driver not attached.

SOCKET_ENOCSI (integer)

No CSI structure available.

SOCKET_EL2HLT (integer)

Level 2 halted.

SOCKET_EBADE (integer)

Invalid exchange.

SOCKET_EBADR (integer)

Invalid request descriptor.

SOCKET_EXFULL (integer)

Exchange full.

SOCKET_ENOANO (integer)

No anode.

SOCKET_EBADRQC (integer)

Invalid request code.

SOCKET_EBADSLT (integer)

Invalid slot.

SOCKET_ENOSTR (integer)

Device not a stream.

SOCKET_ENODATA (integer)

No data available.

SOCKET_ETIME (integer)

Timer expired.

SOCKET_ENOSR (integer)

Out of streams resources.

SOCKET_ENONET (integer)

Machine is not on the network.

SOCKET_ENOLINK (integer)

Link has been severed.

SOCKET_EADV (integer)

Advertise error.

SOCKET_ESRMNT (integer)

Srmount error.

SOCKET_ECOMM (integer)

Communication error on send.

SOCKET_EPROTO (integer)

Protocol error.

SOCKET_EMULTIHOP (integer)

Multihop attempted.

SOCKET_EBADMSG (integer)

Not a data message.

SOCKET_ENOTUNIQ (integer)

Name not unique on network.

SOCKET_EBADFD (integer)

File descriptor in bad state.

SOCKET_EREMCHG (integer)

Remote address changed.

SOCKET_ERESTART (integer)

Interrupted system call should be restarted.

SOCKET_ESTRPIPE (integer)

Streams pipe error.

SOCKET_EPROTOOPT (integer)

Protocol not available.

SOCKET_ADDRINUSE (integer)

Address already in use.

SOCKET_ETOOMANYREFS (integer)

Too many references: cannot splice.

SOCKET_EISNAM (integer)

Is a named type file.

SOCKET_EREMOTEIO (integer)

Remote I/O error.

SOCKET_EDQUOT (integer)

Quota exceeded.

SOCKET_ENOMEDIUM (integer)

No medium found.

SOCKET_EMEDIUMTYPE (integer)

Wrong medium type.