(window.webpackJsonp=window.webpackJsonp||[]).push([[2510],{2918:function(t,s,a){"use strict";a.r(s);var e=a(31),n=Object(e.a)({},(function(){var t=this,s=t.$createElement,a=t._self._c||s;return a("ContentSlotsDistributor",{attrs:{"slot-key":t.$parent.slotKey}},[a("h1",{attrs:{id:"sockets"}},[a("a",{staticClass:"header-anchor",attrs:{href:"#sockets"}},[t._v("#")]),t._v(" Sockets")]),t._v(" "),a("h2",{attrs:{id:"tcp-client-socket"}},[a("a",{staticClass:"header-anchor",attrs:{href:"#tcp-client-socket"}},[t._v("#")]),t._v(" TCP client socket")]),t._v(" "),a("h3",{attrs:{id:"creating-a-socket-that-uses-the-tcp-transmission-control-protocol"}},[a("a",{staticClass:"header-anchor",attrs:{href:"#creating-a-socket-that-uses-the-tcp-transmission-control-protocol"}},[t._v("#")]),t._v(" Creating a socket that uses the TCP (Transmission Control Protocol)")]),t._v(" "),a("div",{staticClass:"language-php extra-class"},[a("pre",{pre:!0,attrs:{class:"language-php"}},[a("code",[a("span",{pre:!0,attrs:{class:"token variable"}},[t._v("$socket")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token operator"}},[t._v("=")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token function"}},[t._v("socket_create")]),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("(")]),a("span",{pre:!0,attrs:{class:"token constant"}},[t._v("AF_INET")]),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(",")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token constant"}},[t._v("SOCK_STREAM")]),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(",")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token constant"}},[t._v("SOL_TCP")]),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(")")]),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(";")]),t._v("\n\n")])])]),a("p",[t._v("Make sure the socket is successfully created. 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This will not affect the original TCP server socket.")]),t._v(" "),a("h3",{attrs:{id:"closing-the-server"}},[a("a",{staticClass:"header-anchor",attrs:{href:"#closing-the-server"}},[t._v("#")]),t._v(" Closing the server")]),t._v(" "),a("p",[t._v("On the other hand, "),a("code",[t._v("socket_close($socket);")]),t._v(" should be called when the server is no longer used. This will free the TCP address as well, allowing other processes to bind to the address.")]),t._v(" "),a("h2",{attrs:{id:"udp-server-socket"}},[a("a",{staticClass:"header-anchor",attrs:{href:"#udp-server-socket"}},[t._v("#")]),t._v(" UDP server socket")]),t._v(" "),a("p",[t._v('A UDP (user datagram protocol) server, unlike TCP, is not stream-based. It is packet-based, i.e. a client sends data in units called "packets" to the server, and the client identifies clients by their address. 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