Attachment #24896 for bug #42473

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	applications, and demand for it rapidly increased across the
	corporation.  Large, high-capacity laser printers designed for office
	printing appeared on the scene.  Printing went from 150 to 300 to
	600 dpi for the common desktop laser printer.</para>

      <para>Today organizational network printing is complex, and printers
	themselves are more complicated.  Most organizations find that sharing

	  user.  Although a single company holding control over a standard can
	  guarantee compliance, it does significantly raise the cost of the
	  printer.  As a result, PostScript has not met with much success in
	  the lower-end laser and inkjet Windows printing market, despite the
	  fact that Adobe distributes PostScript software operating system
	  drivers for free.</para>

	<para>One issue that is a concern when networking PostScript printers
	  is the selection of banner page, (also known as header page, or

	    first defined by Intel and Microsoft and later used by IBM and
	    Microsoft.</para>

	  <para>The LPD protocol is defined in RFC1179.  This network protocol
	    is the standard print protocol used on all UNIX systems.  LPD
	    client implementations exist for all Windows operating systems and
	    DOS.  Microsoft has written LPD for the Windows NT versions, the

	    <para>If the printer is PostScript and cannot print ASCII, make
	      sure that the "No banner page control flag" is checked to turn
	      off banner pages.  Accessible under Port settings, this flag is
	      overridden if the <filename>/etc/printcap</filename> file
	      specifies no banner pages.</para>
	  </step>


	      called with the <option>-c</option> option.  This is equivalent
	      to the local invocation of <filename>/usr/bin/lpr -l</filename>.
	      With the flag checked, the code is F, (formatted) meaning that
	      the <literal>if</literal> filter gets called without the
	      <option>-c</option> option.  This is equivalent to the default
	      invocation <filename>/usr/bin/lpr</filename>.  (This is also an
	      issue under Windows NT, which retypes the print job to text if


	  <step>
	    <para>In the Installed Network Software window, "Microsoft TCP/IP
	      Printing" should be listed as well as "TCP/IP Protocol". If it
	      is, stop here; otherwise continue.</para>
	  </step>
	  
	  <step>

	    Q150930.  With Windows NT 3.51, and 4.0 up to service pack 1 the
	    change is global.  Starting with NT 4.0 Service pack 2 the change
	    can be applied to specific print queues, (see Knowledge Base
	    article ID Q168457). This registry change also works for
	    Windows 2000.</para>

	  <para>Under Windows NT 4.0, the change is:</para>


      <para>Normally, under Windows printing, virtually all graphical programs
	print through the Windows printer driver.  This is true even of basic
	programs such as Notepad.  For example, an administrator may have a
	DOS batch file named <filename>filename.txt</filename> containing the
	following line:</para>

      <programlisting>echo \033&amp;k2G &gt; lpt1:</programlisting>

	printers, as well as defined remote printers. Several programs also
	are used to manipulate jobs in the print spools that LPD manages, as
	well as the user programs to submit them from the UNIX command prompt.
	All of these programs use the <filename>/etc/printcap</filename> file,
	which is the master control file for the printing system.</para>

      <para>Back when printing was mostly text, it was common to place

	description lines are often quite long, they are often written to span
	multiple lines by escaping intermediate newlines with the backslash
	(<literal>\</literal>) character.  The
	<filename>/etc/printcap</filename> file, as supplied, defines a single
	printer queue, <literal>lp</literal>.  The <literal>lp</literal> queue
	is the default queue.  Most UNIX-supplied printing utilities send
	print output to this queue if no printer is specified by the user.  It
	should be set to point to the most popular print queue with
	<emphasis>local</emphasis> UNIX print users, (i.e., users that have
	shell accounts).</para>

      <para>The layout of <filename>/etc/printcap</filename> is covered in the
	manual page, which is reached by running the <userinput>man
	  printcap</userinput> command. The stock
	<filename>/etc/printcap</filename> file at the line defining the spool
	<literal>lp</literal> shows:</para>

      <programlisting>#
lp|local line printer:\

	  directories <emphasis>must</emphasis> be different from each other,
	  or the spooler gets confused and doesen't print.</para>

	<para>After the <filename>/etc/printcap</filename> is modified, the
	  root user must create the <filename>/var/spool/output/NEC</filename>
	  directory and assign ownership of it to the <username>bin</username>
	  user, assign group ownership to <username>daemon</username>, and set

	  <listitem>
	    <para>During FreeBSD installation, if the administrator knows a
	      lot of print jobs are going to go through the spooler,
	      <filename>/var</filename> should be set to a large
		amount of free space.</para>
	  </listitem>


	
	<para>In addition to spools, the following other capabilities are
	  usually placed in a production
	  <filename>/etc/printcap</filename> file.</para>
	
	<para>The entry <literal>fo</literal> prints a form feed when the
	  printer is opened.  It is handy for HPPCL (HP LaserJets) or other

	<para>Hardware print server boxes, such as the HP JetDirect internal
	  and external cards, need some additional capabilities defined in the
	  <filename>/etc/printcap</filename> entry; <literal>rp</literal>, for
	  remote print spool, and <literal>rm</literal> for remote machine
	  name.</para>

	<para>The <literal>rm</literal> capability is simply the DNS or


	<para>The last two important printcap capabilities concern print
	  filters, <literal>if</literal> (input filter) and
	  <literal>of</literal> (output filter).  If defined, incoming print
	  jobs are run through the filters that these entries point to for
	  further processing.</para>


	  <sect4>
	    <title>Output Filters</title>

	    <para>These are specified by the <literal>of</literal> capability.
	      Output filters are much more complicated than input filters and
	      are hardly ever used in normal circumstances.  They also
	      generally require a compiled program somewhere, either directly


	  <para>If the printer is a PostScript printer, and doesn't support
	    standard ASCII, then dumping UNIX text to it doesn't work.  But
	    then, neither would dumping MS-DOS text to it.  (Raw text printing
	    on PostScript printers is discussed later in this chapter.)  Note
	    also that if the printer is connected over the network to an HP
	    JetDirect hardware print server, internal or external, the TEXT
	    queue on the hardware print automatically adds the extra Carriage

	  <para>Although most filters are built by scripts or programs and are
	    added to the UNIX machine by the administrator, there is one
	    filter that is supplied with the FreeBSD operating system is very
	    useful for raw text files: the <literal>pr</literal> filter.  It is
	    most commonly used when printing from the UNIX command shell.  The
	    <literal>pr</literal> filter paginates and applies headers and
	    footers to ASCII text files.  It is automatically invoked with the
	    <option>-p</option> option used with the <command>lpr</command>

	  <para>Unfortunately, the canned banner page supplied in the LPD
	    program prints only on a text-compatible printer.  If the attached
	    printer understands only PostScript and the administrator wants to
	    print banner pages, it is possible to install a filter into the
	    <filename>/etc/printcap</filename> file to do this.</para>

	  <para>The following filter is taken from the FreeBSD Handbook.  I've
	    slightly changed it's invocation for a couple of reasons.  First,


cat &amp;&amp; exit 0</programlisting>

	  <para>Here is the <filename>make-ps-header</filename> listing.</para>

	  <programlisting>#!/bin/sh
# Filename /usr/local/libexec/make-ps-header

	  <para>The username of the submitter can be easily forged, if the job
	    is remotely submitted over the network from a client (practically
	    all jobs in a Windows client printing environment are remotely
	    submitted).  Although some LPR clients can be set to authenticate,
	    and the <literal>rs</literal> capability can be set to enforce
	    authentication, not all can, especially Windows LPR
	    clients.</para>

	model name of the printer, the "Auto printer driver install" feature
	of Windows NT and Win95/98 is activated.  This automatically loads the
	correct printer driver if the user clicks on the print queue in
	Network Neighborhood under Windows 95 or NT 4.0.  The restriction, of
	course, is that the printer model must be in the Windows client driver
	database.</para>


	  generic local line printer.  Since this print queue generally has a
	  filter placed on it to format jobs from the UNIX print queue
	  properly, it should not be visible on the SMB network (i.e., visible
	  in Network Neighborhood).  The second queue,
	  <literal>nec-crlf</literal>, has a filter that converts UNIX text to
	  text that prints without stairstepping, so it also should be hidden
	  from the SMB network.  The third, <literal>nec-raw</literal>, should

	  as a set of defaults for printers that are going to be shared out.
	  Next, the <filename>/etc/printcap</filename> file is read to get a
	  list of all printers on the server.  Last, each printer is checked
	  for a service name in the <filename>smb.conf</filename> file that
	  contains settings that override the set of defaults.</para>

	<para>In the listing of what resources are visible on the network,
	  both <literal>nec-crlf</literal> and <literal>nec-raw</literal>
	  print queues are visible, and <literal>lp</literal> and
	  <literal>nec-ps-banner</literal> is not. <literal>lp</literal> is
	  not visible because there is a specific entry,
	  <literal>[lp]</literal> in the <filename>smb.conf</filename> file

	and Windows NT printing interoperability with NT as a print client
	passing jobs to the FreeBSD system.  What happens if the situation is
	reversed and the FreeBSD system is itself a printing client of another
	LPD server?  This situation can arise in a mixed UNIX/NetWare or
	UNIX/NT environment.  The administrator may elect to forgo the use of
	Samba, and use an NT server to provide print services.  Alternatively,
	the administrator may have existing DOS Novell IPX clients that they

	remotely from an NT server that has LPR installed as a port for it's
	printers.</para>

      <para>Following is a sample <filename>/etc/printcap</filename> file entry
	that defines a print queue named <literal>tank</literal> on the FreeBSD
	system pointed to an NT LPD server queue named
	<literal>sherman</literal> on a NT Server named
	<hostid role="fqdn">big.army.mil</hostid> in the DNS.  This uses the

	  through a filter that allows raw UNIX text sent to it to print
	  properly.  For example, if an HP LaserJet printer that doesn't have
	  PostScript is connected to the server, the
	  <literal>lp</literal> queue specifies in the
	  <filename>/etc/printcap</filename> file the CRLF filter listed
	  earlier.  On the other hand, if an Apple Laserwriter that doesn't
	  support ASCII is connected to the server, the

	    queues are on and view them there.</para>

	  <para>The UNIX shell command used to view the queue is the
	    <command>lpq</command> command.  It is frequently run as
	    <userinput>lpq -a</userinput> which shows jobs in all queues.  The
	    following is a sample output of the command:</para>


	  <para>Just as the root user can manipulate remotely submitted jobs
	    in the print queue, print jobs can be remotely managed by regular
	    users with the LPR clients that created them. Unfortunately, some
	    LPR clients, such as the ACITS LPR client for Win95, don't have
	    enough programming to be able to do this.  Others, like the Win31
	    client, can manipulate the print jobs remotely.</para>

	  <para>FreeBSD offers some level of protection against inadvertent
	    deletion of print jobs from remote hosts by restricting

	<para>The Ghostscript home page is located at
	  <ulink url="http://www.cs.wisc.edu/~ghost/">http://www.cs.wisc.edu/~ghost/</ulink>
	  and contains the most current version of the program.  A prebuilt
	  FreeBSD binary of Ghostscript is located in the Packages section of
	  the FreeBSD CDROM.  This can be installed on the FreeBSD system by
	  selecting the package from the prepackaged software list that is
	  accessed through the <command>/stand/sysinstall</command>
	  installation program.  Many packaged programs on the CD depend on

	  </step>

	  <step>
	    <para>In the <filename>gs5.03</filename> directory, copy the
	      <filename>lprsetup.sh</filename>,
	      <filename>unix-lpr.txt</filename>, and
	      <filename>unix-lpr.sh</filename> files to

	  <step>
	    <para>If the printer that you defined in the
	      <filename>lprsetup.sh</filename> file is a monochrome printer,
	      remove the <literal>"-dBitsPerPixel=${bpp}"</literal> and
	      <literal>"$colorspec"</literal> entries on the
	      <literal>gs</literal> invocation line and save the file.
	      Otherwise, if it is a color definition leave them in.  For

      <sect2>
	<title>a2ps filter</title>

	<para>Another handy utility is the <command>a2ps</command> filter, short
	  for ASCII-to-PostScript.  This program takes an incoming ASCII
	  datastream and converts it into PostScript.  It can also print
	  multiple pages on a single sheet of paper by shrinking them down. It
	  is a useful tool for a printer that cannot interpret ASCII, such as

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