1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> 2 3<html> 4 <head> 5 <meta name="generator" content="HTML Tidy, see www.w3.org"> 6 <title>Data File Transfer</title> 7 <meta name="GENERATOR" content= 8 "Modular DocBook HTML Stylesheet Version 1.7"> 9 <link rel="HOME" title=" LPRng Reference Manual" href= 10 "index.htm"> 11 <link rel="UP" title="RFC 1179 - Line Printer Daemon Protocol " 12 href="rfc1179ref.htm"> 13 <link rel="PREVIOUS" title="Job Transfer " href= 14 "jobtransfer.htm"> 15 <link rel="NEXT" title="Control File Contents" href= 16 "x10227.htm"> 17 </head> 18 19 <body class="SECT1" bgcolor="#FFFFFF" text="#000000" link= 20 "#0000FF" vlink="#840084" alink="#0000FF"> 21 <div class="NAVHEADER"> 22 <table summary="Header navigation table" width="100%" border= 23 "0" cellpadding="0" cellspacing="0"> 24 <tr> 25 <th colspan="3" align="center">LPRng Reference Manual: 5 26 Sep 2003 (For LPRng-3.8.22)</th> 27 </tr> 28 29 <tr> 30 <td width="10%" align="left" valign="bottom"><a href= 31 "jobtransfer.htm" accesskey="P">Prev</a></td> 32 33 <td width="80%" align="center" valign="bottom">Chapter 34 19. RFC 1179 - Line Printer Daemon Protocol</td> 35 36 <td width="10%" align="right" valign="bottom"><a href= 37 "x10227.htm" accesskey="N">Next</a></td> 38 </tr> 39 </table> 40 <hr align="LEFT" width="100%"> 41 </div> 42 43 <div class="SECT1"> 44 <h1 class="SECT1"><a name="AEN10191">19.4. Data File 45 Transfer</a></h1> 46 47 <p>As mentioned before a data file is transferred using the 48 command below.</p> 49 50 <div class="INFORMALTABLE"> 51 <a name="AEN10194"></a> 52 53 <table border="1" frame="border" rules="all" class= 54 "CALSTABLE"> 55 <col> 56 <col> 57 58 <thead> 59 <tr> 60 <th>Command</th> 61 62 <th>Purpose</th> 63 </tr> 64 </thead> 65 66 <tbody> 67 <tr> 68 <td>\003nnnn dfname</td> 69 70 <td>data file transfer</td> 71 </tr> 72 </tbody> 73 </table> 74 </div> 75 <br> 76 <br> 77 78 <p>From RFC1179: <a name="AEN10205"></a></p> 79 80 <blockquote class="BLOCKQUOTE"> 81 <p>The data file may contain any 8 bit values at all. The 82 total number of bytes in the stream may be sent as the 83 first operand, otherwise the field should be cleared to 0. 84 The name of the data file should start with ASCII "dfA". 85 This should be followed by a three digit job number. The 86 job number should be followed by the host name which has 87 constructed the data file. Interpretation of the contents 88 of the data file is determined by the contents of the 89 corresponding control file.</p> 90 </blockquote> 91 <br> 92 <br> 93 94 <p>There are several surprises in RFC1179.</p> 95 96 <ol type="1"> 97 <li> 98 <p>Apparently a job should only consist of a single data 99 file. This is a severe limitation, and in fact the BSD <b 100 class="APPLICATION">lpr</b> and other print spoolers 101 process jobs with multiple data files. By convention, 102 these data files have names of the form <var class= 103 "LITERAL">dfA</var>, <var class="LITERAL">dfB</var>, ... 104 <var class="LITERAL">dfZ</var>, <var class= 105 "LITERAL">dfa</var>, <var class="LITERAL">dfz</var>.</p> 106 </li> 107 108 <li> 109 <p>The RFC does not specify that the control file and 110 data file job numbers must be identical. Most 111 implementations follow this convention, which simplifies 112 life tremendously.</p> 113 </li> 114 115 <li> 116 <p>The RFC does not specify that the control file and 117 data file job host names must be identical. Most 118 implementations follow this convention, which simplifies 119 life tremendously.</p> 120 </li> 121 122 <li> 123 <p>A zero length data file does not cause a data transfer 124 to take place. <b class="APPLICATION">LPRng</b> modifies 125 this action to be slightly different. When a zero length 126 data file transfer is indicated, all of the input until 127 the connection is closed is used as the contents of the 128 data file.</p> 129 130 <p>When <span class="emphasis"><i class= 131 "EMPHASIS">piping</i></span> into the <b class= 132 "APPLICATION">lpr</b> program, this can be very useful as 133 it eliminates the need to create temporary files on the 134 local host. Note that some print spoolers do not use this 135 interpretation, and this option should be used 136 carefully.</p> 137 </li> 138 </ol> 139 <br> 140 <br> 141 </div> 142 143 <div class="NAVFOOTER"> 144 <hr align="LEFT" width="100%"> 145 146 <table summary="Footer navigation table" width="100%" border= 147 "0" cellpadding="0" cellspacing="0"> 148 <tr> 149 <td width="33%" align="left" valign="top"><a href= 150 "jobtransfer.htm" accesskey="P">Prev</a></td> 151 152 <td width="34%" align="center" valign="top"><a href= 153 "index.htm" accesskey="H">Home</a></td> 154 155 <td width="33%" align="right" valign="top"><a href= 156 "x10227.htm" accesskey="N">Next</a></td> 157 </tr> 158 159 <tr> 160 <td width="33%" align="left" valign="top">Job 161 Transfer</td> 162 163 <td width="34%" align="center" valign="top"><a href= 164 "rfc1179ref.htm" accesskey="U">Up</a></td> 165 166 <td width="33%" align="right" valign="top">Control File 167 Contents</td> 168 </tr> 169 </table> 170 </div> 171 </body> 172</html> 173 174