source/texk/web2c/luatexdir/luasocket/doc/dns.html

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  37 <!-- dns ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->
  38
  39 <h2 id=dns>DNS</h2>
  40
  41 <p>
  42 IPv4 name resolution functions
  43 <a href=#toip><tt>dns.toip</tt></a>
  44 and
  45 <a href=#tohostname><tt>dns.tohostname</tt></a>
  46 return <em>all</em> information obtained from
  47 the resolver in a table of the form:
  48 </p>
  49
  50 <blockquote><tt>
  51 resolved4 = {<br>
  52 &nbsp;&nbsp;name = <i>canonic-name</i>,<br>
  53 &nbsp;&nbsp;alias = <i>alias-list</i>,<br>
  54 &nbsp;&nbsp;ip = <i>ip-address-list</i><br>
  55 }
  56 </tt> </blockquote>
  57
  58 <p>
  59 Note that the <tt>alias</tt> list can be empty.
  60 </p>
  61
  62 <p>
  63 The more general name resolution function
  64 <a href=#getaddrinfo><tt>dns.getaddrinfo</tt></a>, which
  65 supports both IPv6 and IPv4,
  66 returns <em>all</em> information obtained from
  67 the resolver in a table of the form:
  68 </p>
  69
  70 <blockquote><tt>
  71 resolved6 = {<br>
  72 &nbsp;&nbsp;[1] = {<br>
  73 &nbsp;&nbsp;&nbsp;&nbsp;family = <i>family-name-1</i>,<br>
  74 &nbsp;&nbsp;&nbsp;&nbsp;addr = <i>address-1</i><br>
  75 &nbsp;&nbsp;},<br>
  76 &nbsp;&nbsp;...<br>
  77 &nbsp;&nbsp;[n] = {<br>
  78 &nbsp;&nbsp;&nbsp;&nbsp;family = <i>family-name-n</i>,<br>
  79 &nbsp;&nbsp;&nbsp;&nbsp;addr = <i>address-n</i><br>
  80 &nbsp;&nbsp;}<br>
  81 }
  82 </tt> </blockquote>
  83
  84 <p>
  85 Here, <tt>family</tt> contains the string <tt>"inet"</tt> for IPv4
  86 addresses, and <tt>"inet6"</tt> for IPv6 addresses.
  87 </p>
  88
  89 <!-- getaddrinfo ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->
  90
  91 <p class=name id=getaddrinfo>
  92 socket.dns.<b>getaddrinfo(</b>address<b>)</b>
  93 </p>
  94
  95 <p class=description>
  96 Converts from host name to address.
  97 </p>
  98
  99 <p class=parameters>
 100 <tt>Address</tt> can  be an IPv4 or IPv6 address or host name.
 101 </p>
 102
 103 <p class=return>
 104 The function returns a table with  all  information returned  by
 105 the  resolver.  In  case of error, the function returns <b><tt>nil</tt></b>
 106 followed by an error message.
 107 </p>
 108
 109 <!-- gethostname ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->
 110
 111 <p class=name id=gethostname>
 112 socket.dns.<b>gethostname()</b>
 113 </p>
 114
 115 <p class=description>
 116 Returns the standard host name for the machine as a string.
 117 </p>
 118
 119 <!-- tohostname +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->
 120
 121 <p class=name id=tohostname>
 122 socket.dns.<b>tohostname(</b>address<b>)</b>
 123 </p>
 124
 125 <p class=description>
 126 Converts from IPv4 address to host name.
 127 </p>
 128
 129 <p class=parameters>
 130 <tt>Address</tt> can  be an IP address  or host name.
 131 </p>
 132
 133 <p class=return>
 134 The function returns a string  with the canonic host name of the given
 135 <tt>address</tt>, followed  by a  table with  all  information returned  by
 136 the  resolver.  In  case of error, the function returns <b><tt>nil</tt></b>
 137 followed by an error message.
 138 </p>
 139
 140 <!-- toip +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -->
 141
 142 <p class=name id=toip>
 143 socket.dns.<b>toip(</b>address<b>)</b>
 144 </p>
 145
 146 <p class=description>
 147 Converts from host name to IPv4 address.
 148 </p>
 149
 150 <p class=parameters>
 151 <tt>Address</tt> can  be an IP address  or host name.
 152 </p>
 153
 154 <p class=return>
 155 Returns a string  with the first IP address  found for <tt>address</tt>,
 156 followed  by a  table with  all  information returned  by the  resolver.
 157 In  case of error, the function returns <b><tt>nil</tt></b> followed by an error
 158 message.
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 175 Last modified by Diego Nehab on <br>
 176 Thu Apr 20 00:25:07 EDT 2006
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