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spooling directory with the <var class="LITERAL">sd</var> capability:</p>

<pre class="PROGRAMLISTING">
#
#  /etc/printcap for host rose - added spooling directories
#
rattan|line|diablo|lp|Diablo 630 Line Printer:\
        :sh:sd=/var/spool/lpd/rattan:

bamboo|ps|PS|S|panasonic|Panasonic KX-P4455 PostScript v51.4:\
        :sh:sd=/var/spool/lpd/bamboo:
</pre>

<p>Note that the name of the printer starts in the first column but all other entries
describing the printer should be indented with a tab and each line escaped with a
backslash.</p>

<p>If you do not specify a spooling directory with <var class="LITERAL">sd</var>, the
spooling system will use <tt class="FILENAME">/var/spool/lpd</tt> as a default.</p>
</div>

<div class="SECT4">
<h4 class="SECT4"><a id="PRINTING-DEVICE" name="PRINTING-DEVICE">9.3.1.4.4. Identifying
the Printer Device</a></h4>

<p>In the <a href="printing-intro-setup.html#PRINTING-DEV-PORTS">Adding <tt
class="FILENAME">/dev</tt> Entries for the Ports</a> section, we identified which entry
in the <tt class="FILENAME">/dev</tt> directory FreeBSD will use to communicate with the
printer. Now, we tell <b class="APPLICATION">LPD</b> that information. When the spooling
system has a job to print, it will open the specified device on behalf of the filter
program (which is responsible for passing data to the printer).</p>

<p>List the <tt class="FILENAME">/dev</tt> entry pathname in the <tt
class="FILENAME">/etc/printcap</tt> file using the <var class="LITERAL">lp</var>
capability.</p>

<p>In our running example, let us assume that <var class="LITERAL">rattan</var> is on the
first parallel port, and <var class="LITERAL">bamboo</var> is on a sixth serial port;
here are the additions to <tt class="FILENAME">/etc/printcap</tt>:</p>

<pre class="PROGRAMLISTING">
#
#  /etc/printcap for host rose - identified what devices to use
#
rattan|line|diablo|lp|Diablo 630 Line Printer:\
        :sh:sd=/var/spool/lpd/rattan:\
        :lp=/dev/lpt0:

bamboo|ps|PS|S|panasonic|Panasonic KX-P4455 PostScript v51.4:\
        :sh:sd=/var/spool/lpd/bamboo:\
        :lp=/dev/ttyd5:
</pre>

<p>If you do not specify the <var class="LITERAL">lp</var> capability for a printer in
your <tt class="FILENAME">/etc/printcap</tt> file, <b class="APPLICATION">LPD</b> uses
<tt class="FILENAME">/dev/lp</tt> as a default. <tt class="FILENAME">/dev/lp</tt>
currently does not exist in FreeBSD.</p>

<p>If the printer you are installing is connected to a parallel port, skip to the section
entitled, <a href="printing-intro-setup.html#PRINTING-TEXTFILTER">Installing the Text
Filter</a>. Otherwise, be sure to follow the instructions in the next section.</p>
</div>

<div class="SECT4">
<h4 class="SECT4"><a id="PRINTING-COMMPARAM" name="PRINTING-COMMPARAM">9.3.1.4.5.
Configuring Spooler Communication Parameters</a></h4>

<p>For printers on serial ports, <b class="APPLICATION">LPD</b> can set up the bps rate,
parity, and other serial communication parameters on behalf of the filter program that
sends data to the printer. This is advantageous since:</p>

<ul>
<li>
<p>It lets you try different communication parameters by simply editing the <tt
class="FILENAME">/etc/printcap</tt> file; you do not have to recompile the filter
program.</p>
</li>

<li>
<p>It enables the spooling system to use the same filter program for multiple printers
which may have different serial communication settings.</p>
</li>
</ul>

<p>The following <tt class="FILENAME">/etc/printcap</tt> capabilities control serial
communication parameters of the device listed in the <var class="LITERAL">lp</var>
capability:</p>

<div class="VARIABLELIST">
<dl>
<dt><var class="LITERAL">br#<var class="REPLACEABLE">bps-rate</var></var></dt>

<dd>
<p>Sets the communications speed of the device to <var
class="REPLACEABLE">bps-rate</var>, where <var class="REPLACEABLE">bps-rate</var> can be
50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800, 9600, 19200, 38400, 57600,
or 115200 bits-per-second.</p>
</dd>

<dt><var class="LITERAL">ms#<var class="REPLACEABLE">stty-mode</var></var></dt>

<dd>
<p>Sets the options for the terminal device after opening the device. <span
class="CITEREFENTRY"><span class="REFENTRYTITLE">stty</span>(1)</span> explains the
available options.</p>
</dd>
</dl>
</div>

<p>When <b class="APPLICATION">LPD</b> opens the device specified by the <var
class="LITERAL">lp</var> capability, it sets the characteristics of the device to those
specified with the <var class="LITERAL">ms#</var> capability. Of particular interest will
be the <var class="LITERAL">parenb</var>, <var class="LITERAL">parodd</var>, <var
class="LITERAL">cs5</var>, <var class="LITERAL">cs6</var>, <var
class="LITERAL">cs7</var>, <var class="LITERAL">cs8</var>, <var
class="LITERAL">cstopb</var>, <var class="LITERAL">crtscts</var>, and <var
class="LITERAL">ixon</var> modes, which are explained in the <span
class="CITEREFENTRY"><span class="REFENTRYTITLE">stty</span>(1)</span> manual page.</p>

<p>Let us add to our example printer on the sixth serial port. We will set the bps rate
to 38400. For the mode, we will set no parity with <var class="LITERAL">-parenb</var>,
8-bit characters with <var class="LITERAL">cs8</var>, no modem control with <var
class="LITERAL">clocal</var> and hardware flow control with <var
class="LITERAL">crtscts</var>:</p>

<pre class="PROGRAMLISTING">
bamboo|ps|PS|S|panasonic|Panasonic KX-P4455 PostScript v51.4:\
        :sh:sd=/var/spool/lpd/bamboo:\
        :lp=/dev/ttyd5:ms#-parenb cs8 clocal crtscts:
</pre>
</div>

<div class="SECT4">
<h4 class="SECT4"><a id="PRINTING-TEXTFILTER" name="PRINTING-TEXTFILTER">9.3.1.4.6.
Installing the Text Filter</a></h4>

<p>We are now ready to tell <b class="APPLICATION">LPD</b> what text filter to use to
send jobs to the printer. A <span class="emphasis"><i class="EMPHASIS">text
filter</i></span>, also known as an <span class="emphasis"><i class="EMPHASIS">input
filter</i></span>, is a program that <b class="APPLICATION">LPD</b> runs when it has a
job to print. When <b class="APPLICATION">LPD</b> runs the text filter for a printer, it
sets the filter's standard input to the job to print, and its standard output to the
printer device specified with the <var class="LITERAL">lp</var> capability. The filter is
expected to read the job from standard input, perform any necessary translation for the
printer, and write the results to standard output, which will get printed. For more
information on the text filter, see the <a
href="printing-advanced.html#PRINTING-ADVANCED-FILTERS">Filters</a> section.</p>

<p>For our simple printer setup, the text filter can be a small shell script that just
executes <tt class="COMMAND">/bin/cat</tt> to send the job to the printer. FreeBSD comes
with another filter called <tt class="FILENAME">lpf</tt> that handles backspacing and
underlining for printers that might not deal with such character streams well. And, of
course, you can use any other filter program you want. The filter <tt
class="COMMAND">lpf</tt> is described in detail in section entitled <a
href="printing-advanced.html#PRINTING-ADVANCED-LPF">lpf: a Text Filter</a>.</p>

<p>First, let us make the shell script <tt
class="FILENAME">/usr/local/libexec/if-simple</tt> be a simple text filter. Put the
following text into that file with your favorite text editor:</p>

<pre class="PROGRAMLISTING">
#!/bin/sh
#
# if-simple - Simple text input filter for lpd
# Installed in /usr/local/libexec/if-simple
#
# Simply copies stdin to stdout.  Ignores all filter arguments.

/bin/cat &amp;&amp; exit 0
exit 2
</pre>

<p>Make the file executable:</p>

<pre class="SCREEN">
<samp class="PROMPT">#</samp> <kbd
class="USERINPUT">chmod 555 /usr/local/libexec/if-simple</kbd>
</pre>

<p>And then tell LPD to use it by specifying it with the <var class="LITERAL">if</var>
capability in <tt class="FILENAME">/etc/printcap</tt>. We will add it to the two printers
we have so far in the example <tt class="FILENAME">/etc/printcap</tt>:</p>

<pre class="PROGRAMLISTING">
#
#  /etc/printcap for host rose - added text filter
#
rattan|line|diablo|lp|Diablo 630 Line Printer:\
        :sh:sd=/var/spool/lpd/rattan:\ :lp=/dev/lpt0:\
        :if=/usr/local/libexec/if-simple:

bamboo|ps|PS|S|panasonic|Panasonic KX-P4455 PostScript v51.4:\
        :sh:sd=/var/spool/lpd/bamboo:\
        :lp=/dev/ttyd5:ms#-parenb cs8 clocal crtscts:\
        :if=/usr/local/libexec/if-simple:
</pre>

<div class="NOTE">
<blockquote class="NOTE">
<p><b>注:</b> A copy of the <tt class="FILENAME">if-simple</tt> script can be found in
the <tt class="FILENAME">/usr/share/examples/printing</tt> directory.</p>
</blockquote>
</div>
</div>

<div class="SECT4">
<h4 class="SECT4"><a id="AEN11016" name="AEN11016">9.3.1.4.7. Turn on <b
class="APPLICATION">LPD</b></a></h4>

<p><span class="CITEREFENTRY"><span class="REFENTRYTITLE">lpd</span>(8)</span> is run
from <tt class="FILENAME">/etc/rc</tt>, controlled by the <var
class="LITERAL">lpd_enable</var> variable. This variable defaults to <var
class="LITERAL">NO</var>. If you have not done so already, add the line:</p>

<pre class="PROGRAMLISTING">
lpd_enable="YES"
</pre>

<p>to <tt class="FILENAME">/etc/rc.conf</tt>, and then either restart your machine, or
just run <span class="CITEREFENTRY"><span class="REFENTRYTITLE">lpd</span>(8)</span>.</p>

<pre class="SCREEN">
<samp class="PROMPT">#</samp> <kbd class="USERINPUT">lpd</kbd>
</pre>
</div>

<div class="SECT4">
<h4 class="SECT4"><a id="PRINTING-TRYING" name="PRINTING-TRYING">9.3.1.4.8. Trying It
Out</a></h4>

<p>You have reached the end of the simple <b class="APPLICATION">LPD</b> setup.
Unfortunately, congratulations are not quite yet in order, since we still have to test
the setup and correct any problems. To test the setup, try printing something. To print
with the <b class="APPLICATION">LPD</b> system, you use the command <span
class="CITEREFENTRY"><span class="REFENTRYTITLE">lpr</span>(1)</span>, which submits a
job for printing.</p>

<p>You can combine <span class="CITEREFENTRY"><span
class="REFENTRYTITLE">lpr</span>(1)</span> with the <span class="CITEREFENTRY"><span
class="REFENTRYTITLE">lptest</span>(1)</span> program, introduced in section <a
href="printing-intro-setup.html#PRINTING-TESTING">Checking Printer Communications</a> to
generate some test text.</p>

<p><span class="emphasis"><i class="EMPHASIS">To test the simple <b
class="APPLICATION">LPD</b> setup:</i></span></p>

<p>Type:</p>

<pre class="SCREEN">
<samp class="PROMPT">#</samp> <kbd class="USERINPUT">lptest 20 5 | lpr -P<var
class="REPLACEABLE">printer-name</var></kbd>
</pre>

<p>Where <var class="REPLACEABLE">printer-name</var> is a the name of a printer (or an
alias) specified in <tt class="FILENAME">/etc/printcap</tt>. To test the default printer,
type <span class="CITEREFENTRY"><span class="REFENTRYTITLE">lpr</span>(1)</span> without
any <var class="OPTION">-P</var> argument. Again, if you are testing a printer that
expects <span class="TRADEMARK">PostScript</span>, send a <span
class="TRADEMARK">PostScript</span> program in that language instead of using <span
class="CITEREFENTRY"><span class="REFENTRYTITLE">lptest</span>(1)</span>. You can do so
by putting the program in a file and typing <tt class="COMMAND">lpr <var
class="REPLACEABLE">file</var></tt>.</p>

<p>For a <span class="TRADEMARK">PostScript</span> printer, you should get the results of
the program. If you are using <span class="CITEREFENTRY"><span
class="REFENTRYTITLE">lptest</span>(1)</span>, then your results should look like the
following:</p>

<pre class="PROGRAMLISTING">
!"#$%&amp;'()*+,-./01234
"#$%&amp;'()*+,-./012345
#$%&amp;'()*+,-./0123456
$%&amp;'()*+,-./01234567
%&amp;'()*+,-./012345678
</pre>

<p>To further test the printer, try downloading larger programs (for language-based
printers) or running <span class="CITEREFENTRY"><span
class="REFENTRYTITLE">lptest</span>(1)</span> with different arguments. For example, <tt
class="COMMAND">lptest 80 60</tt> will produce 60 lines of 80 characters each.</p>

<p>If the printer did not work, see the <a
href="printing-troubleshooting.html">Troubleshooting</a> section.</p>
</div>
</div>
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