1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
|
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta name="generator" content="HTML Tidy, see www.w3.org">
<title>Print Spooling Tutorial</title>
<meta name="GENERATOR" content=
"Modular DocBook HTML Stylesheet Version 1.71 ">
<link rel="HOME" title=" LPRng-HOWTO" href="index.htm">
<link rel="PREVIOUS" title="AppleTalk Support " href=
"appletalk.htm">
<link rel="NEXT" title="Sample Printcap Entry" href=
"sampleprintcap.htm">
</head>
<body class="CHAPTER" bgcolor="#FFFFFF" text="#000000" link=
"#0000FF" vlink="#840084" alink="#0000FF">
<div class="NAVHEADER">
<table summary="Header navigation table" width="100%" border=
"0" cellpadding="0" cellspacing="0">
<tr>
<th colspan="3" align="center">LPRng-HOWTO: 1 Apr 2002
(For LPRng-3.8.10)</th>
</tr>
<tr>
<td width="10%" align="left" valign="bottom"><a href=
"appletalk.htm" accesskey="P">Prev</a></td>
<td width="80%" align="center" valign="bottom">
</td>
<td width="10%" align="right" valign="bottom"><a href=
"sampleprintcap.htm" accesskey="N">Next</a></td>
</tr>
</table>
<hr align="LEFT" width="100%">
</div>
<div class="CHAPTER">
<h1><a name="TUTORIAL">Chapter 4. Print Spooling
Tutorial</a></h1>
<div class="TOC">
<dl>
<dt><b>Table of Contents</b></dt>
<dt>4.1. <a href=
"tutorial.htm#OVERVIEW">Overview</a></dt>
<dt>4.2. <a href="sampleprintcap.htm">Sample Printcap
Entry</a></dt>
<dt>4.3. <a href="tutorialconfig.htm">Setting Up the
Tutorial Configuration</a></dt>
<dt>4.4. <a href="restoring.htm">Restoring Original
Configuration</a></dt>
<dt>4.5. <a href="printingandchecking.htm">Printing a
File and Checking Status</a></dt>
<dt>4.6. <a href="selectingprintqueue.htm">Selecting the
Print Queue</a></dt>
<dt>4.7. <a href="controllingprintqueue.htm">Controlling
the Print Queue</a></dt>
<dt>4.8. <a href="jobremoval.htm">Job Removal</a></dt>
<dt>4.9. <a href="printjobfilters.htm">Print Job
Filters</a></dt>
<dt>4.10. <a href="jobfileformatconversion.htm">Job File
Format Conversion with Filters</a></dt>
<dt>4.11. <a href="x3050.htm">Printcap Basics</a></dt>
<dt>4.12. <a href="x3220.htm">Banner Printing and the OF
filter</a></dt>
<dt>4.13. <a href="x3323.htm">Printing from <b class=
"APPLICATION">lpr</b> Directly To A Device</a></dt>
<dt>4.14. <a href="x3370.htm">Moving Jobs From Queue to
Queue and Redirecting Queues</a></dt>
<dt>4.15. <a href="x3417.htm">Print Job Classes, User
Requested Job Priority, and Form Support</a></dt>
<dt>4.16. <a href="x3462.htm">Holding and Releasing
Jobs</a></dt>
<dt>4.17. <a href="x3540.htm">Load Balance Queues and
Printer Pools</a></dt>
<dt>4.18. <a href="x3641.htm">Routing Jobs To Print
Queues</a></dt>
<dt>4.19. <a href="x3714.htm">Job Options and the Z
Control File Entry</a></dt>
<dt>4.20. <a href="x3832.htm">Interfacing to Non-LPRng
Spoolers</a></dt>
<dt>4.21. <a href="x3864.htm">Debugging, Tracing, and Log
Files</a></dt>
</dl>
</div>
<p>A print spooler is a program that accepts <i class=
"EMPHASIS">print jobs</i> (which are usually one or more
files) from a program or network interface, stores them in a
<i class="EMPHASIS">spool queue</i>, and then sends them to a
printer or another print spooler. Usually there are
facilities to submit jobs, check on the current job status,
remove jobs from spool queues, and perform administrative
functions such as starting or stopping printing.</p>
<p>A print spooler is a client/server application. The client
programs are used to submit jobs to the print spooler program
which performs the actual printing operations. In order to
carry out these operations, the server may need to use other
programs to convert print job files into a format acceptable
to a printer, or perform various accounting or administrative
functions.</p>
<div class="SECT1">
<h1 class="SECT1"><a name="OVERVIEW">4.1. Overview</a></h1>
<div class="INFORMALEXAMPLE">
<a name="AEN1615"></a>
<pre class="SCREEN">
+---------+ +-----+ +-----+ +--------+ +---------+
| program | -> | lpr | -> | lpd | -> | filter | -> | printer |
+---------+ +-----+ * +-----+ +--------+ +---------+
* * |
printcap V
+-----+ +--------+ +---------+
| lpd | -> | filter | -> | printer |
+-----+ +--------+ +---------+
Figure 1
</pre>
</div>
<br>
<br>
<p>Figure 1 shows the flow of data between the individual
components of the <b class="APPLICATION">LPRng</b> print
spooling system. A program (or user) will use the <b class=
"APPLICATION">lpr</b> program to send a file to the <b
class="APPLICATION">lpd</b> server over a TCP/IP
connection. The <b class="APPLICATION">lpd</b> server will
store the file temporarily in a spool queue directory. The
information needed by the <b class="APPLICATION">lpr</b>
and <b class="APPLICATION">lpd</b> programs to carry out
this activity is stored in the <tt class=
"FILENAME">printcap</tt> (usually called the <tt class=
"FILENAME">/etc/printcap</tt>) database file.</p>
<p>The <b class="APPLICATION">lpd</b> server sorts the
queue entries and determines the print order. It will
select a job to be printed, open a connection to the
printer, and then use a <i class="EMPHASIS">filter</i>
program to convert the file contents into a format suitable
for the printer. If the file does not need conversion, then
the <b class="APPLICATION">lpd</b> server will send the
file directly to the printer.</p>
<p>The <b class="APPLICATION">lpd</b> server can also <i
class="EMPHASIS">forward</i> jobs to another print server
over a network connection, optionally sending them through
a filter as well. The destination server can in turn
forward the job or send it to a printer.</p>
<p>The protocol or commands used to do this job forward and
transfer are specified by <a href=
"rfc1179ref.htm">RFC1179</a>. This protocol specifies how
the <b class="APPLICATION">lpr</b> client program sends a
job to the <b class="APPLICATION">lpd</b> server, as well
as how the <b class="APPLICATION">lpd</b> server forwards
jobs to another server. In addition to job submission,
RFC1179 specifies commands to obtain queue status, to
remove jobs from the queue, and to start and stop print
queues.</p>
</div>
</div>
<div class="NAVFOOTER">
<hr align="LEFT" width="100%">
<table summary="Footer navigation table" width="100%" border=
"0" cellpadding="0" cellspacing="0">
<tr>
<td width="33%" align="left" valign="top"><a href=
"appletalk.htm" accesskey="P">Prev</a></td>
<td width="34%" align="center" valign="top"><a href=
"index.htm" accesskey="H">Home</a></td>
<td width="33%" align="right" valign="top"><a href=
"sampleprintcap.htm" accesskey="N">Next</a></td>
</tr>
<tr>
<td width="33%" align="left" valign="top">AppleTalk
Support</td>
<td width="34%" align="center" valign="top"> </td>
<td width="33%" align="right" valign="top">Sample
Printcap Entry</td>
</tr>
</table>
</div>
</body>
</html>
|
