SOCKET_CREATE(3)							 1							  SOCKET_CREATE(3)

socket_create - Create a socket (endpoint for communication)

SYNOPSIS

       resource socket_create (int  $domain, int  $type, int  $protocol)

DESCRIPTION

	Creates  and  returns  a  socket  resource, also referred to as an endpoint of communication. A typical network connection is made up of 2
       sockets, one performing the role of the client, and another performing the role of the server.

PARAMETERS

	      o $domain
		- The $domain parameter specifies the protocol family to be used by the socket.

	      Available address/protocol families

	      +---------+---------------------------------------------------+
	      | Domain	|						    |
	      | 	|						    |
	      | 	|		     Description		    |
	      | 	|						    |
	      +---------+---------------------------------------------------+
	      | 	|						    |
	      |AF_INET	|						    |
	      | 	|						    |
	      | 	|  IPv4 Internet based protocols. TCP and  UDP	are |
	      | 	| common protocols of this protocol family.	    |
	      | 	|						    |
	      | 	|						    |
	      |AF_INET6 |						    |
	      | 	|						    |
	      | 	|  IPv6  Internet  based protocols. TCP and UDP are |
	      | 	| common protocols of this protocol family.	    |
	      | 	|						    |
	      | 	|						    |
	      |AF_UNIX	|						    |
	      | 	|						    |
	      | 	|  Local communication protocol family. High  effi- |
	      | 	| ciency  and  low overhead make it a great form of |
	      | 	| IPC (Interprocess Communication).		    |
	      | 	|						    |
	      +---------+---------------------------------------------------+
	      o $type
		- The $type parameter selects the type of communication to be used by the socket.

	      Available socket types

	      +---------------+---------------------------------------------------+
	      |     Type      | 						  |
	      | 	      | 						  |
	      | 	      | 		   Description			  |
	      | 	      | 						  |
	      +---------------+---------------------------------------------------+
	      | 	      | 						  |
	      | SOCK_STREAM   | 						  |
	      | 	      | 						  |
	      | 	      |  Provides sequenced, reliable, full-duplex,  con- |
	      | 	      | nection-based  byte  streams. An out-of-band data |
	      | 	      | transmission mechanism may be supported. The  TCP |
	      | 	      | protocol is based on this socket type.		  |
	      | 	      | 						  |
	      | 	      | 						  |
	      |  SOCK_DGRAM   | 						  |
	      | 	      | 						  |
	      | 	      |  Supports  datagrams  (connectionless, unreliable |
	      | 	      | messages of a fixed maximum length). The UDP pro- |
	      | 	      | tocol is based on this socket type.		  |
	      | 	      | 						  |
	      | 	      | 						  |
	      |SOCK_SEQPACKET | 						  |
	      | 	      | 						  |
	      | 	      |  Provides  a sequenced, reliable, two-way connec- |
	      | 	      | tion-based data transmission path  for	datagrams |
	      | 	      | of  fixed  maximum length; a consumer is required |
	      | 	      | to read an entire packet with each read call.	  |
	      | 	      | 						  |
	      | 	      | 						  |
	      |   SOCK_RAW    | 						  |
	      | 	      | 						  |
	      | 	      |  Provides raw network protocol access. This  spe- |
	      | 	      | cial  type of socket can be used to manually con- |
	      | 	      | struct any type of protocol.  A  common  use  for |
	      | 	      | this  socket  type  is	to  perform ICMP requests |
	      | 	      | (like ping).					  |
	      | 	      | 						  |
	      | 	      | 						  |
	      |   SOCK_RDM    | 						  |
	      | 	      | 						  |
	      | 	      |  Provides a reliable datagram layer that does not |
	      | 	      | guarantee  ordering.  This  is	most  likely  not |
	      | 	      | implemented on your operating system.		  |
	      | 	      | 						  |
	      +---------------+---------------------------------------------------+
	      o $protocol
		- The $protocol parameter sets the specific protocol within the specified $domain to be used when communicating  on  the  returned
		socket.  The  proper  value can be retrieved by name by using getprotobyname(3). If the desired protocol is TCP, or UDP the corre-
		sponding constants SOL_TCP, and SOL_UDP can also be used.

	      Common protocols

	      +-----+---------------------------------------------------+
	      |Name |							|
	      |     |							|
	      |     |			 Description			|
	      |     |							|
	      +-----+---------------------------------------------------+
	      |icmp |							|
	      |     |							|
	      |     |  The Internet Control Message  Protocol  is  used |
	      |     | primarily  by gateways and hosts to report errors |
	      |     | in datagram  communication.  The	"ping"	command |
	      |     | (present	in most modern operating systems) is an |
	      |     | example application of ICMP.			|
	      |     |							|
	      |udp  |							|
	      |     |							|
	      |     |  The User Datagram Protocol is a	connectionless, |
	      |     | unreliable,  protocol  with fixed record lengths. |
	      |     | Due to these  aspects,  UDP  requires  a	minimum |
	      |     | amount of protocol overhead.			|
	      |     |							|
	      |tcp  |							|
	      |     |							|
	      |     |  The Transmission Control Protocol is a reliable, |
	      |     | connection based, stream	oriented,  full  duplex |
	      |     | protocol.  TCP  guarantees  that all data packets |
	      |     | will be received in the order in which they  were |
	      |     | sent. If any packet is somehow lost during commu- |
	      |     | nication, TCP will automatically	retransmit  the |
	      |     | packet  until  the  destination host acknowledges |
	      |     | that packet. For reliability and performance rea- |
	      |     | sons,  the  TCP implementation itself decides the |
	      |     | appropriate octet boundaries  of	the  underlying |
	      |     | datagram	 communication	layer.	Therefore,  TCP |
	      |     | applications must allow for  the	possibility  of |
	      |     | partial record transmission.			|
	      |     |							|
	      +-----+---------------------------------------------------+
RETURN VALUES

       socket_create(3)  returns  a  socket  resource  on  success,  or  FALSE	on  error.  The  actual  error	code  can  be retrieved by calling
       socket_last_error(3). This error code may be passed to socket_strerror(3) to get a textual explanation of the error.

ERRORS
/EXCEPTIONS
	If an invalid $domain or $type is given, socket_create(3) defaults to AF_INET and  SOCK_STREAM	respectively  and  additionally  emits	an
       E_WARNING message.

SEE ALSO

       socket_accept(3), socket_bind(3), socket_connect(3), socket_listen(3), socket_last_error(3), socket_strerror(3).

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