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 (int)

AF_INET (int)

AF_INET6 (int)

Only available if compiled with IPv6 support.

SOCK_STREAM (int)

SOCK_DGRAM (int)

SOCK_RAW (int)

SOCK_SEQPACKET (int)

SOCK_RDM (int)

MSG_OOB (int)

MSG_WAITALL (int)

MSG_PEEK (int)

MSG_DONTROUTE (int)

MSG_EOR (int)

Not available on Windows platforms.

MSG_EOF (int)

Not available on Windows platforms.

SO_DEBUG (int)

SO_REUSEADDR (int)

SO_REUSEPORT (int)

This constant is only available on platforms that support the SO_REUSEPORT socket option: this includes Linux, macOS and *BSD, but does not include Windows.

SO_KEEPALIVE (int)

SO_DONTROUTE (int)

SO_LINGER (int)

SO_BROADCAST (int)

SO_OOBINLINE (int)

SO_SNDBUF (int)

SO_RCVBUF (int)

SO_SNDLOWAT (int)

SO_RCVLOWAT (int)

SO_SNDTIMEO (int)

SO_RCVTIMEO (int)

SO_TYPE (int)

SO_ERROR (int)

TCP_NODELAY (int)

Used to disable Nagle TCP algorithm.

SO_MARK (int)

Available as of PHP 8.1.0

SO_USER_COOKIE (int)

Available as of PHP 8.1.0

SO_ACCEPTFILTER (string)

Available as of PHP 8.1.0

SO_DONTTRUNC (int)

Available as of PHP 8.1.0

SO_WANTMORE (int)

Available as of PHP 8.1.0

TCP_DEFER_ACCEPT (int)

Available as of PHP 8.1.0

SOL_SOCKET (int)

PHP_NORMAL_READ (int)

PHP_BINARY_READ (int)

SOL_TCP (int)

SOL_UDP (int)

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 (int)

Interrupted system call.

SOCKET_EBADF (int)

Bad file descriptor number.

SOCKET_EACCES (int)

Permission denied.

SOCKET_EFAULT (int)

Bad address.

SOCKET_EINVAL (int)

Invalid argument.

SOCKET_EMFILE (int)

Too many open files.

SOCKET_ENAMETOOLONG (int)

File name too long.

SOCKET_ENOTEMPTY (int)

Directory not empty.

SOCKET_ELOOP (int)

Too many symbolic links encountered.

SOCKET_EWOULDBLOCK (int)

Operation would block.

SOCKET_EREMOTE (int)

Object is remote.

SOCKET_EUSERS (int)

Too many users.

SOCKET_ENOTSOCK (int)

Socket operation on non-socket.

SOCKET_EDESTADDRREQ (int)

Destination address required.

SOCKET_EMSGSIZE (int)

Message too long.

SOCKET_EPROTOTYPE (int)

Protocol wrong type for socket.

SOCKET_EPROTONOSUPPORT (int)

Protocol not supported.

SOCKET_ESOCKTNOSUPPORT (int)

Socket type not supported.

SOCKET_EOPNOTSUPP (int)

Operation not supported on transport endpoint.

SOCKET_EPFNOSUPPORT (int)

Protocol family not supported.

SOCKET_EAFNOSUPPORT (int)

Address family not supported by protocol.

SOCKET_EADDRNOTAVAIL (int)

Cannot assign requested address.

SOCKET_ENETDOWN (int)

Network is down.

SOCKET_ENETUNREACH (int)

Network is unreachable.

SOCKET_ENETRESET (int)

Network dropped connection because of reset.

SOCKET_ECONNABORTED (int)

Software caused connection abort.

SOCKET_ECONNRESET (int)

Connection reset by peer.

SOCKET_ENOBUFS (int)

No buffer space available.

SOCKET_EISCONN (int)

Transport endpoint is already connected.

SOCKET_ENOTCONN (int)

Transport endpoint is not connected.

SOCKET_ESHUTDOWN (int)

Cannot send after transport endpoint shutdown.

SOCKET_ETIMEDOUT (int)

Connection timed out.

SOCKET_ECONNREFUSED (int)

Connection refused.

SOCKET_EHOSTDOWN (int)

Host is down.

SOCKET_EHOSTUNREACH (int)

No route to host.

SOCKET_EALREADY (int)

Operation already in progress.

SOCKET_EINPROGRESS (int)

Operation now in progress.

The following constants are only defined under Windows.

SOCKET_ENOPROTOOPT (int)

SOCKET_EADDRINUSE (int)

SOCKET_ETOOMYREFS (int)

SOCKET_EPROCLIM (int)

SOCKET_EDUOT (int)

SOCKET_ESTALE (int)

SOCKET_EDISCON (int)

SOCKET_SYSNOTREADY (int)

SOCKET_VERNOTSUPPORTED (int)

SOCKET_NOTINITIALISED (int)

SOCKET_HOST_NOT_FOUND (int)

SOCKET_TRY_AGAIN (int)

SOCKET_NO_RECOVERY (int)

SOCKET_NO_DATA (int)

SOCKET_NO_ADDRESS (int)

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 (int)

Operation not permitted.

SOCKET_ENOENT (int)

No such file or directory.

SOCKET_EIO (int)

I/O error.

SOCKET_ENXIO (int)

No such device or address.

SOCKET_E2BIG (int)

Arg list too long.

SOCKET_EAGAIN (int)

Try again.

SOCKET_ENOMEM (int)

Out of memory.

SOCKET_ENOTBLK (int)

Block device required.

SOCKET_EBUSY (int)

Device or resource busy.

SOCKET_EEXIST (int)

File exists.

SOCKET_EXDEV (int)

Cross-device link.

SOCKET_ENODEV (int)

No such device.

SOCKET_ENOTDIR (int)

Not a directory.

SOCKET_EISDIR (int)

Is a directory.

SOCKET_ENFILE (int)

File table overflow.

SOCKET_ENOTTY (int)

Not a typewriter.

SOCKET_ENOSPC (int)

No space left on device.

SOCKET_ESPIPE (int)

Illegal seek.

SOCKET_EROFS (int)

Read-only file system.

SOCKET_EMLINK (int)

Too many links.

SOCKET_EPIPE (int)

Broken pipe.

SOCKET_ENOLCK (int)

No record locks available.

SOCKET_ENOSYS (int)

Function not implemented.

SOCKET_ENOMSG (int)

No message of desired type.

SOCKET_EIDRM (int)

Identifier removed.

SOCKET_ECHRNG (int)

Channel number out of range.

SOCKET_EL2NSYNC (int)

Level 2 not synchronized.

SOCKET_EL3HLT (int)

Level 3 halted.

SOCKET_EL3RST (int)

Level 3 reset.

SOCKET_ELNRNG (int)

Link number out of range.

SOCKET_EUNATCH (int)

Protocol driver not attached.

SOCKET_ENOCSI (int)

No CSI structure available.

SOCKET_EL2HLT (int)

Level 2 halted.

SOCKET_EBADE (int)

Invalid exchange.

SOCKET_EBADR (int)

Invalid request descriptor.

SOCKET_EXFULL (int)

Exchange full.

SOCKET_ENOANO (int)

No anode.

SOCKET_EBADRQC (int)

Invalid request code.

SOCKET_EBADSLT (int)

Invalid slot.

SOCKET_ENOSTR (int)

Device not a stream.

SOCKET_ENODATA (int)

No data available.

SOCKET_ETIME (int)

Timer expired.

SOCKET_ENOSR (int)

Out of streams resources.

SOCKET_ENONET (int)

Machine is not on the network.

SOCKET_ENOLINK (int)

Link has been severed.

SOCKET_EADV (int)

Advertise error.

SOCKET_ESRMNT (int)

Srmount error.

SOCKET_ECOMM (int)

Communication error on send.

SOCKET_EPROTO (int)

Protocol error.

SOCKET_EMULTIHOP (int)

Multihop attempted.

SOCKET_EBADMSG (int)

Not a data message.

SOCKET_ENOTUNIQ (int)

Name not unique on network.

SOCKET_EBADFD (int)

File descriptor in bad state.

SOCKET_EREMCHG (int)

Remote address changed.

SOCKET_ERESTART (int)

Interrupted system call should be restarted.

SOCKET_ESTRPIPE (int)

Streams pipe error.

SOCKET_EPROTOOPT (int)

Protocol not available.

SOCKET_ADDRINUSE (int)

Address already in use.

SOCKET_ETOOMANYREFS (int)

Too many references: cannot splice.

SOCKET_EISNAM (int)

Is a named type file.

SOCKET_EREMOTEIO (int)

Remote I/O error.

SOCKET_EDQUOT (int)

Quota exceeded.

SOCKET_ENOMEDIUM (int)

No medium found.

SOCKET_EMEDIUMTYPE (int)

Wrong medium type.

SCM_RIGHTS (int)

Send or receive a set of open file descriptors from another process.

SCM_CREDENTIALS (int)