Attachment 6195 Details for Bug 14237 – file.diff

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>Index: article.sgml
>===================================================================
>RCS file: /home/nbm/ncvs/doc/en_US.ISO_8859-1/articles/programming-tools/article.sgml,v
>retrieving revision 1.8
>diff -u -r1.8 article.sgml
>--- article.sgml	1999/10/04 22:04:28	1.8
>+++ article.sgml	1999/10/09 14:26:02
>@@ -118,13 +118,12 @@
> 
> <para>To get one of these packages, all you need to do is to click on
> the hotlink for the package, then run
>-<screen>$ <userinput>pkg_add <replaceable>package name</></userinput></screen>
> </para>
>+<screen>&prompt.root; <userinput>pkg_add <replaceable>package name</></userinput></screen>
>   
> <para>as root. Obviously, you will need to have a fully functional FreeBSD
> 2.1.0 or later system for the package to work!</para>
>   
>-<para>
> <variablelist>
> <varlistentry><term><acronym>BASIC</></term>
> 
>@@ -206,7 +205,6 @@
> </varlistentry>
> 
> </variablelist>
>-</para>
>   
> </sect2>
> 
>@@ -309,13 +307,14 @@
> <para>Fortunately, almost all this detail is hidden from you, as
> <command>cc</> is a front end that manages calling all these programs
> with the right arguments for you; simply typing
>-<screen>$ <userinput>cc foobar.c</></screen></para>
>+</para>
>+<screen>&prompt.user; <userinput>cc foobar.c</></screen>
>   
> <para>will cause <filename>foobar.c</> to be compiled by all the
> steps above. If you have more than one file to compile, just do
> something like
>-<screen>$ <userinput>cc foo.c bar.c</></screen>
> </para>
>+<screen>&prompt.user; <userinput>cc foo.c bar.c</></screen>
>   
> <para>Note that the syntax checking is just that&mdash;checking the
> syntax. It will not check for any logical mistakes you may have made,
>@@ -337,8 +336,8 @@
> the mists of history.</para></footnote></para>
> 
> <informalexample>
>-<screen>$ <userinput>cc foobar.c</>               <lineannotation>executable is <filename>a.out</></>
>-$ <userinput>cc -o foobar foobar.c</>     <lineannotation>executable is <filename>foobar</></></screen>
>+<screen>&prompt.user; <userinput>cc foobar.c</>               <lineannotation>executable is <filename>a.out</></>
>+&prompt.user; <userinput>cc -o foobar foobar.c</>     <lineannotation>executable is <filename>foobar</></></screen>
> </informalexample>
> </listitem>
> </varlistentry>
>@@ -349,7 +348,7 @@
> a <filename>Makefile</filename>.</para>
> 
> <informalexample>
>-<screen>$ <userinput>cc -c foobar.c</userinput></screen>
>+<screen>&prompt.user; <userinput>cc -c foobar.c</userinput></screen>
> </informalexample>
>   
> <para>This will produce an <firstterm>object file</> (not an
>@@ -373,7 +372,7 @@
> works properly.</para>
> 
> <informalexample>
>-<screen>$ <userinput>cc -g foobar.c</userinput></screen>
>+<screen>&prompt.user; <userinput>cc -g foobar.c</userinput></screen>
> </informalexample>
>   
> <para>This will produce a debug version of the
>@@ -401,7 +400,7 @@
> version.</para>
> 
> <informalexample>
>-<screen>$ <userinput>cc -O -o foobar foobar.c</userinput></screen>
>+<screen>&prompt.user; <userinput>cc -O -o foobar foobar.c</userinput></screen>
> </informalexample>
>   
> <para>This will produce an optimised version of
>@@ -461,7 +460,7 @@
> what you may be using in a few years time?</para>
>   
> <informalexample>
>-<screen>$ <userinput>cc -Wall -ansi -pedantic -o foobar foobar.c</userinput></screen>
>+<screen>&prompt.user; <userinput>cc -Wall -ansi -pedantic -o foobar foobar.c</userinput></screen>
> </informalexample>
> 
> <para>This will produce an executable <filename>foobar</filename>
>@@ -490,7 +489,7 @@
> last library on the command line.</para>
> 
> <informalexample>
>-<screen>$ <userinput>cc -o foobar foobar.c -lm</userinput></screen>
>+<screen>&prompt.user; <userinput>cc -o foobar foobar.c -lm</userinput></screen>
> </informalexample>
> 
> <para>This will link the math library functions into
>@@ -505,9 +504,9 @@
> on FreeBSD.</para>
> 
> <informalexample>
>-<screen>$ <userinput>cc -o foobar foobar.cc -lg++</userinput>     <lineannotation>For FreeBSD 2.1.6 and earlier</>
>-$ <userinput>cc -o foobar foobar.cc -lstdc++</userinput>  <lineannotation>For FreeBSD 2.2 and later</>
>-$ <userinput>c++ -o foobar foobar.cc</userinput></screen>
>+<screen>&prompt.user; <userinput>cc -o foobar foobar.cc -lg++</userinput>     <lineannotation>For FreeBSD 2.1.6 and earlier</>
>+&prompt.user; <userinput>cc -o foobar foobar.cc -lstdc++</userinput>  <lineannotation>For FreeBSD 2.2 and later</>
>+&prompt.user; <userinput>c++ -o foobar foobar.cc</userinput></screen>
> </informalexample>
> 
> <para>Each of these will both produce an executable
>@@ -529,23 +528,31 @@
> <sect2>
> <title>Common <command>cc</command> Queries and Problems</title>
> 
>-<para>Q. I am trying to write a program which uses the
>+<qandaset>
>+<qandaentry>
>+<question>
>+<para>I am trying to write a program which uses the
> <function>sin()</function> function and I get an error like this.
> What does it mean?
>+</para>
> <informalexample>
> <screen>/var/tmp/cc0143941.o: Undefined symbol `_sin' referenced from text segment</screen>
> </informalexample>
>-</para>
>-  
>-<para>A. When using mathematical functions like
>+</question>
>+<answer>
>+<para>When using mathematical functions like
> <function>sin()</function>, you have to tell <command>cc</command> to
>-link in the math library, like so:
>+link in the math library, like so:</para>
> <informalexample>
>-<screen>$ <userinput>cc -o foobar foobar.c -lm</userinput></screen>
>-</informalexample></para>
>-
>-<para>Q. All right, I wrote this simple program to practice using
>+<screen>&prompt.user; <userinput>cc -o foobar foobar.c -lm</userinput></screen>
>+</informalexample>
>+</answer>
>+</qandaentry>
>+<qandaentry>
>+<question>
>+<para>All right, I wrote this simple program to practice using
> <option>-lm</option>. All it does is raise 2.1 to the power of 6.
>+</para>
> <informalexample>
> <programlisting>#include &lt;stdio.h&gt;
> 
>@@ -557,31 +564,40 @@
> 	return 0;
> }</programlisting>
> </informalexample>
>+<para>
> and I compiled it as:
>+</para>
> <informalexample>
>-<screen>$ <userinput>cc temp.c -lm</userinput></screen>
>+<screen>&prompt.user; <userinput>cc temp.c -lm</userinput></screen>
> </informalexample>
>+<para>
> like you said I should, but I get this when I run it:
>+</para>
> <informalexample>
>-<screen>$ <userinput>./a.out</userinput>
>+<screen>&prompt.user; <userinput>./a.out</userinput>
> 2.1 ^ 6 = 1023.000000</screen>
> </informalexample>
>-</para>
>   
> <para>This is <emphasis>not</emphasis> the right answer! What is
> going on?</para>
>-
>-<para>A. When the compiler sees you call a function, it checks if it
>+</question>
>+<answer>
>+<para>When the compiler sees you call a function, it checks if it
> has already seen a prototype for it. If it has not, it assumes the
> function returns an <type>int</type>, which is
> definitely not what you want here.</para>
>-
>-<para>Q. So how do I fix this?</para>
>-  
>-<para>A. The prototypes for the mathematical functions are in
>+</answer>
>+</qandaentry>
>+<qandaentry>
>+<question>
>+<para>So how do I fix this?</para>
>+</question>
>+<answer>
>+<para>The prototypes for the mathematical functions are in
> <filename>math.h</filename>. If you include this file, the compiler
> will be able to find the prototype and it will stop doing strange
> things to your calculation!
>+</para>
> <informalexample>
> <programlisting>#include &lt;math.h&gt;
> #include &lt;stdio.h&gt;
>@@ -589,94 +605,125 @@
> int main() {
> ...</programlisting>
> </informalexample>
>-</para>
>   
> <para>After recompiling it as you did before, run it:
>+</para>
> <informalexample>
>-<screen>$ <userinput>./a.out</userinput>
>+<screen>&prompt.user; <userinput>./a.out</userinput>
> 2.1 ^ 6 = 85.766121</screen>
> </informalexample>
>-</para>
>   
> <para>If you are using any of the mathematical functions,
> <emphasis>always</emphasis> include <filename>math.h</filename> and
> remember to link in the math library.</para>
>-
>-<para>Q. I compiled a file called <filename>foobar.c</filename> and I
>+</answer>
>+</qandaentry>
>+<qandaentry>
>+<question>
>+<para>I compiled a file called <filename>foobar.c</filename> and I
> cannot find an executable called <filename>foobar</filename>. Where's
> it gone?</para>
>-
>-<para>A. Remember, <command>cc</command> will call the executable
>+</question>
>+<answer>
>+<para>Remember, <command>cc</command> will call the executable
> <filename>a.out</filename> unless you tell it differently. Use the
> <option>-o&nbsp;<replaceable>filename</replaceable></option> option:
>+</para>
> <informalexample>
>-<screen>$ <userinput>cc -o foobar foobar.c</userinput></screen>
>+<screen>&prompt.user; <userinput>cc -o foobar foobar.c</userinput></screen>
> </informalexample>
>-</para>
>-
>-<para>Q. OK, I have an executable called <filename>foobar</filename>,
>+</answer>
>+</qandaentry>
>+<qandaentry>
>+<question>
>+<para>OK, I have an executable called <filename>foobar</filename>,
> I can see it when I run <command>ls</command>, but when I type in
> <command>foobar</command> at the command prompt it tells me there is
> no such file. Why can it not find it?</para>
>-
>-<para>A. Unlike <trademark>MS-DOS</trademark>, Unix does not look in the
>+</question>
>+<answer>
>+<para>Unlike <trademark>MS-DOS</trademark>, Unix does not look in the
> current directory when it is trying to find out which executable you
> want it to run, unless you tell it to. Either type
> <command>./foobar</command>, which means <quote>run the file called
> <filename>foobar</filename> in the current directory</quote>, or
> change your <systemitem class=environvar>PATH</systemitem>
> environment variable so that it looks something like
>+</para>
> <informalexample>
> <screen>bin:/usr/bin:/usr/local/bin:.</screen>
> </informalexample>
>+<para>
> The dot at the end means <quote>look in the current directory if it is not in
> any of the others</quote>.</para>
>-  
>-<para>Q. I called my executable <filename>test</filename>, but
>+</answer>
>+</qandaentry>
>+<qandaentry>
>+<question> 
>+<para>I called my executable <filename>test</filename>, but
> nothing happens when I run it. What is going on?</para>
>-
>-<para>A. Most Unix systems have a program called
>+</question>
>+<answer>
>+<para>Most Unix systems have a program called
> <command>test</command> in <filename>/usr/bin</filename> and the
> shell is picking that one up before it gets to checking the current
> directory. Either type:
>+</para>
> <informalexample>
>-<screen>$ <userinput>./test</userinput></screen>
>+<screen>&prompt.user; <userinput>./test</userinput></screen>
> </informalexample>
>+<para>
> or choose a better name for your program!</para>
>-  
>-<para>Q. I compiled my program and it seemed to run all right at
>+</answer>
>+</qandaentry>
>+<qandaentry>
>+<question>
>+<para>I compiled my program and it seemed to run all right at
> first, then there was an error and it said something about <errorname>core
> dumped</errorname>. What does that mean?</para>
>-
>-<para>A. The name <firstterm>core dump</firstterm> dates back to the
>+</question>
>+<answer>
>+<para>The name <firstterm>core dump</firstterm> dates back to the
> very early days of Unix, when the machines used core memory for
> storing data. Basically, if the program failed under certain
> conditions, the system would write the contents of core memory to
> disk in a file called <filename>core</filename>, which the programmer
> could then pore over to find out what went wrong.</para>
>-
>-<para>Q. Fascinating stuff, but what I am supposed to do now?</para>
>-  
>-<para>A. Use <command>gdb</command> to analyse the core (see <xref
>+</answer>
>+</qandaentry>
>+<qandaentry>
>+<question>
>+<para>Fascinating stuff, but what I am supposed to do now?</para>
>+</question>
>+<answer>
>+<para>Use <command>gdb</command> to analyse the core (see <xref
> linkend="debugging">).</para>
>-  
>-<para>Q. When my program dumped core, it said something about a
>+</answer>
>+</qandaentry>
>+<qandaentry>
>+<question>
>+<para>When my program dumped core, it said something about a
> <errorname>segmentation fault</errorname>. What's that?</para>
>-
>-<para>A. This basically means that your program tried to perform some sort
>+</question>
>+<answer>
>+<para>This basically means that your program tried to perform some sort
> of illegal operation on memory; Unix is designed to protect the
> operating system and other programs from rogue programs.</para>
>   
> <para>Common causes for this are:
>+</para>
> <itemizedlist>
> <listitem><para>Trying to write to a <symbol>NULL</symbol> pointer, eg
>+</para>
> <programlisting>char *foo = NULL;
> strcpy(foo, "bang!");</programlisting>
>-</para></listitem>
>+</listitem>
> 
> <listitem><para>Using a pointer that hasn't been initialised, eg
>+</para>
> <programlisting>char *foo;
> strcpy(foo, "bang!");</programlisting>
>+<para>
> The pointer will have some random value that, with luck,
> will point into an area of memory that isn't available to
> your program and the kernel will kill your program before
>@@ -686,51 +733,68 @@
> mysteriously.</para></listitem>
> 
> <listitem><para>Trying to access past the end of an array, eg
>+</para>
> <programlisting>int bar[20];
>-bar[27] = 6;</programlisting></para></listitem>
>+bar[27] = 6;</programlisting></listitem>
> 
> <listitem><para> Trying to store something in read-only memory, eg
>+</para>
> <programlisting>char *foo = "My string";
> strcpy(foo, "bang!");</programlisting>
>+<para>
> Unix compilers often put string literals like
> <literal>"My string"</literal> into
> read-only areas of memory.</para></listitem>
> 
> <listitem><para>Doing naughty things with
> <function>malloc()</function> and <function>free()</function>, eg
>+</para>
> <programlisting>char bar[80];
> free(bar);</programlisting>
>+<para>
> or
>+</para>
> <programlisting>char *foo = malloc(27);
> free(foo);
> free(foo);</programlisting>
>-</para></listitem>
>+</listitem>
> 
>-</itemizedlist></para>
>+</itemizedlist>
> 
> <para>Making one of these mistakes will not always lead to an
> error, but they are always bad practice. Some systems and
> compilers are more tolerant than others, which is why programs
> that ran well on one system can crash when you try them on an
> another.</para>
>-  
>-<para>Q. Sometimes when I get a core dump it says <errorname>bus
>+</answer>
>+</qandaentry>
>+<qandaentry>
>+<question>
>+<para>Sometimes when I get a core dump it says <errorname>bus
> error</errorname>. It says in my Unix book that this means a hardware
> problem, but the computer still seems to be working. Is this
> true?</para>
>-
>-<para>A. No, fortunately not (unless of course you really do have a hardware
>+</question>
>+<answer>
>+<para>No, fortunately not (unless of course you really do have a hardware
> problem&hellip;). This is usually another way of saying that you
> accessed memory in a way you shouldn't have.</para>
>-  
>-<para>Q. This dumping core business sounds as though it could be quite
>+</answer>
>+</qandaentry>
>+<qandaentry>
>+<question>
>+<para>This dumping core business sounds as though it could be quite
> useful, if I can make it happen when I want to. Can I do this, or
> do I have to wait until there's an error?</para>
>-  
>-<para>A. Yes, just go to another console or xterm, do
>-<screen>$ <userinput>ps</userinput></screen>
>+</question>
>+<answer>
>+<para>Yes, just go to another console or xterm, do</para>
>+<screen>&prompt.user; <userinput>ps</userinput></screen>
>+<para>
> to find out the process ID of your program, and do
>-<screen>$ <userinput>kill -ABRT <replaceable>pid</replaceable></userinput></screen>
>+</para>
>+<screen>&prompt.user; <userinput>kill -ABRT <replaceable>pid</replaceable></userinput></screen>
>+<para>
> where <parameter><replaceable>pid</replaceable></parameter> is the
> process ID you looked up.</para>
>   
>@@ -738,6 +802,9 @@
> loop, for instance. If your program happens to trap
> <symbol>SIGABRT</symbol>, there are several other signals which have
> a similar effect.</para>
>+</answer>
>+</qandaentry>
>+</qandaset>
> 
> </sect2>
> </sect1>
>@@ -751,14 +818,18 @@
> 
> <para>When you're working on a simple program with only one or two source
> files, typing in
>-<screen>$ <userinput>cc file1.c file2.c</userinput></screen>
>+</para>
>+<screen>&prompt.user; <userinput>cc file1.c file2.c</userinput></screen>
>+<para>
> is not too bad, but it quickly becomes very tedious when there are
> several files&mdash;and it can take a while to compile, too.</para>
>   
> <para>One way to get around this is to use object files and only recompile
> the source file if the source code has changed. So we could have
> something like:
>-<screen>$ <userinput>cc file1.o file2.o</userinput> &hellip; <userinput>file37.c</userinput> &hellip</screen>
>+</para>
>+<screen>&prompt.user; <userinput>cc file1.o file2.o</userinput> &hellip; <userinput>file37.c</userinput> &hellip</screen>
>+<para>
> if we'd changed <filename>file37.c</filename>, but not any of the
> others, since the last time we compiled.  This may speed up the
> compilation quite a bit, but  doesn't solve the typing
>@@ -805,8 +876,10 @@
> <title>Example of using <command>make</command></title>
> 
> <para>Here's a very simple make file:
>+</para>
> <programlisting>foo: foo.c
> 	cc -o foo foo.c</programlisting>
>+<para>
> It consists of two lines, a dependency line and a creation line.</para>
>   
> <para>The dependency line here consists of the name of the program
>@@ -840,14 +913,17 @@
> <para>Another useful property of makefiles is that the targets don't have
> to be programs. For instance, we could have a make file that looks
> like this:
>+</para>
> <programlisting>foo: foo.c
> 	cc -o foo foo.c
> 
> install:
>-	cp foo /home/me</programlisting></para>
>+	cp foo /home/me</programlisting>
>   
> <para>We can tell make which target we want to make by typing:
>-<screen>$ <userinput>make <replaceable>target</replaceable></userinput></screen>
>+</para>
>+<screen>&prompt.user; <userinput>make <replaceable>target</replaceable></userinput></screen>
>+<para>
> <command>make</command> will then only look at that target and ignore any
> others. For example, if we type <userinput>make foo</userinput> with the 
> makefile above, make will ignore the <action>install</action> target.</para>
>@@ -886,11 +962,11 @@
> BSD-based systems like FreeBSD come with some very powerful ones as
> part of the system.  One very good example of this is the FreeBSD
> ports system. Here's the essential part of a typical ports
>-<filename>Makefile</filename>:
>+<filename>Makefile</filename>:</para>
> <programlisting>MASTER_SITES=   ftp://freefall.cdrom.com/pub/FreeBSD/LOCAL_PORTS/
> DISTFILES=      scheme-microcode+dist-7.3-freebsd.tgz
> 
>-.include &lt;bsd.port.mk&gt;</programlisting></para>
>+.include &lt;bsd.port.mk&gt;</programlisting>
>   
> <para>Now, if we go to the directory for this port and type
> <userinput>make</userinput>, the following happens:</para>
>@@ -965,7 +1041,9 @@
> <para>The version of make that comes with FreeBSD is the <application>Berkeley
> make</application>; there is a tutorial for it in
> <filename>/usr/share/doc/psd/12.make</filename>. To view it, do
>-<screen>$ <userinput>zmore paper.ascii.gz</userinput></screen>
>+</para>
>+<screen>&prompt.user; <userinput>zmore paper.ascii.gz</userinput></screen>
>+<para>
> in that directory.</para>
>   
> <para>Many applications in the ports use <application>GNU
>@@ -979,7 +1057,9 @@
> you will have to edit the <filename>dir</filename> file in the
> <filename>/usr/local/info</filename> directory to add an entry for
> it. This involves adding a line like
>+</para>
> <programlisting> * Make: (make).                 The GNU Make utility.</programlisting>
>+<para>
> to the file. Once you have done this, you can type
> <userinput>info</userinput> and then select
> <guimenuitem>make</guimenuitem> from the menu (or in
>@@ -998,10 +1078,13 @@
> <para>The debugger that comes with FreeBSD is called
> <command>gdb</command> (<application>GNU
> debugger</application>). You start it up by typing
>-<screen>$ <userinput>gdb <replaceable>progname</replaceable></userinput></screen>
>+</para>
>+<screen>&prompt.user; <userinput>gdb <replaceable>progname</replaceable></userinput></screen>
>+<para>
> although most people prefer to run it inside
> <application>Emacs</application>. You can do this by:
>-<screen><userinput>M-x gdb RET <replaceable>progname</replaceable> RET</userinput></screen></para>
>+</para>
>+<screen><userinput>M-x gdb RET <replaceable>progname</replaceable> RET</userinput></screen>
>   
> <para>Using a debugger allows you to run the program under more
> controlled circumstances. Typically, you can step through the program
>@@ -1035,7 +1118,8 @@
> <command>gdb</command>. It will work without, but you'll only see the
> name of the function you're in, instead of the source code. If you
> see a line like:
>-<screen>&hellip; (no debugging symbols found) &hellip;</screen>when
>+</para>
>+<screen>&hellip; (no debugging symbols found) &hellip;</screen><para>when
> <command>gdb</command> starts up, you'll know that the program wasn't
> compiled with the <option>-g</option> option.</para>
>   
>@@ -1058,6 +1142,7 @@
> <para>Here's a simple example of how to spot a mistake in a program
> with <command>gdb</command>. This is our program (with a deliberate
> mistake):
>+</para>
> <programlisting>#include &lt;stdio.h&gt;
> 
> int bazz(int anint);
>@@ -1074,20 +1159,20 @@
> 	printf("You gave me %d\n", anint);
> 	return anint;
> }</programlisting>
>-</para>
>   
> <para>This program sets <symbol>i</symbol> to be <literal>5</literal>
> and passes it to a function <function>bazz()</function> which prints
> out the number we gave it.</para>
> 
> <para>When we compile and run the program we get
>-<screen>$ <userinput>cc -g -o temp temp.c</userinput>
>-$ <userinput>./temp</userinput>
>+</para>
>+<screen>&prompt.user; <userinput>cc -g -o temp temp.c</userinput>
>+&prompt.user; <userinput>./temp</userinput>
> This is my program
>-anint = 4231</screen></para>
>+anint = 4231</screen>
>   
> <para>That wasn't what we expected! Time to see what's going
>-on!<screen>$ <userinput>gdb temp</userinput>
>+on!</para><screen>&prompt.user; <userinput>gdb temp</userinput>
> GDB is free software and you are welcome to distribute copies of it
>  under certain conditions; type "show copying" to see the conditions.
> There is absolutely no warranty for GDB; type "show warranty" for details.
>@@ -1102,7 +1187,7 @@
> This is my program				<lineannotation>Program prints out</>
> (gdb) <userinput>s</>						<lineannotation>step into <function>bazz()</></>
> bazz (anint=4231) at temp.c:17			<lineannotation><command>gdb</command> displays stack frame</>
>-(gdb)</screen></para>
>+(gdb)</screen>
> 
>   
> <para>Hang on a minute! How did <symbol>anint</symbol> get to be
>@@ -1110,12 +1195,15 @@
> in <function>main()</function>? Let's move up to
> <function>main()</function> and have a look.</para>
> 
>-<para><screen>(gdb) <userinput>up</>					<lineannotation>Move up call stack</>
>+<screen>(gdb) <userinput>up</>					<lineannotation>Move up call stack</>
> #1  0x1625 in main () at temp.c:11		<lineannotation><command>gdb</command> displays stack frame</>
> (gdb) <userinput>p i</>					<lineannotation>Show us the value of <symbol>i</></>
>-$1 = 4231					<lineannotation><command>gdb</command> displays <literal>4231</></></screen>
>+$1 = 4231					<lineannotation><command>gdb</command> displays <literal>4231</></>
>+</screen>
>+<para>
> Oh dear! Looking at the code, we forgot to initialise
> <symbol>i</symbol>. We meant to put
>+</para>
> <programlisting><lineannotation>&hellip;</>
> main() {
> 	int i;
>@@ -1123,6 +1211,7 @@
> 	i = 5;
> 	printf("This is my program\n");
> <lineannotation>&hellip</></programlisting>
>+<para>
> but we left the <literal>i=5;</literal> line out.  As we didn't
> initialise <symbol>i</symbol>, it had whatever number happened to be
> in that area of memory when the program ran, which in this case
>@@ -1154,12 +1243,15 @@
> <para>To examine a core file, start up <command>gdb</command> in the
> usual way. Instead of typing <command>break</command> or
> <command>run</command>, type
>+</para>
> <screen>(gdb) <userinput>core <replaceable>progname</replaceable>.core</userinput></screen>
>+<para>
> If you're not in the same directory as the core file, you'll have to
> do <userinput>dir /path/to/core/file</userinput> first.</para>
>   
> <para>You should see something like this:
>-<screen>$ <userinput>gdb a.out</userinput>
>+</para>
>+<screen>&prompt.user; <userinput>gdb a.out</userinput>
> GDB is free software and you are welcome to distribute copies of it
>  under certain conditions; type "show copying" to see the conditions.
> There is absolutely no warranty for GDB; type "show warranty" for details.
>@@ -1169,7 +1261,7 @@
> Program terminated with signal 11, Segmentation fault.
> Cannot access memory at address 0x7020796d.
> #0  0x164a in bazz (anint=0x5) at temp.c:17
>-(gdb)</screen></para>
>+(gdb)</screen>
>   
> <para>In this case, the program was called
> <filename>a.out</filename>, so the core file is called
>@@ -1182,11 +1274,12 @@
> stack in a complex program. The <command>bt</command> command causes
> <command>gdb</command> to print out a back-trace of the call
> stack:
>+</para>
> <screen>(gdb) <userinput>bt</userinput>
> #0  0x164a in bazz (anint=0x5) at temp.c:17
> #1  0xefbfd888 in end ()
> #2  0x162c in main () at temp.c:11
>-(gdb)</screen>The <function>end()</function> function is called when
>+(gdb)</screen><para>The <function>end()</function> function is called when
> a program crashes; in this case, the <function>bazz()</function>
> function was called from <function>main()</function>.</para>
> 
>@@ -1204,13 +1297,15 @@
> 
> <para>What you do is start up another <command>gdb</command>, use
> <command>ps</command> to find the process ID for the child, and
>-do<screen>(gdb) <userinput>attach <replaceable>pid</replaceable></userinput></screen>  
>+do</para><screen>(gdb) <userinput>attach <replaceable>pid</replaceable></userinput></screen>  
>+<para>
> in <command>gdb</command>, and then debug as usual.</para>
>   
> <para><quote>That's all very well,</quote> you're probably thinking,
> <quote>but by the time I've done that, the child process will be over
> the hill and far away</quote>. Fear not, gentle reader, here's how to
> do it (courtesy of the <command>gdb</command> info pages):
>+</para>
> <screen><lineannotation>&hellip</lineannotation>
> if ((pid = fork()) < 0)		/* _Always_ check this */
> 	error();
>@@ -1222,6 +1317,7 @@
> 	<lineannotation>&hellip</lineannotation>
> } else {			/* parent */
> 	<lineannotation>&hellip</lineannotation></screen>
>+<para>
> Now all you have to do is attach to the child, set
> <symbol>PauseMode</symbol> to <literal>0</literal>, and
> wait for the <function>sleep()</function> call to return!</para>
>@@ -1259,6 +1355,7 @@
> 
> <para>It's impossible even to summarise everything Emacs can do here, but
> here are some of the features of interest to developers:
>+</para>
> <itemizedlist>
> 
> <listitem><para>Very powerful editor, allowing search-and-replace on
>@@ -1289,7 +1386,7 @@
> <listitem><para>You can read Usenet news and mail while your program
> is compiling.</para></listitem>
> 
>-</itemizedlist>And doubtless many more that I've overlooked.</para>
>+</itemizedlist><para>And doubtless many more that I've overlooked.</para>
> 
> <para>Emacs can be installed on FreeBSD using <ulink
> URL="../../ports/editors.html">the Emacs
>@@ -1386,7 +1483,6 @@
> <para>Unfortunately, there's far too much here to explain it in detail;
> however there are one or two points worth mentioning.</para>
>   
>-<para>
> <itemizedlist>
> 
> <listitem><para>Everything beginning with a <literal>;</> is a
>@@ -1423,7 +1519,9 @@
> <listitem><para> We enable Emacs's ability to act as a server, so
> that if you're doing something outside Emacs and you want to edit a
> file, you can just type in 
>-<screen>$ <userinput>emacsclient <replaceable>filename</replaceable></userinput></screen>
>+</para>
>+<screen>&prompt.user; <userinput>emacsclient <replaceable>filename</replaceable></userinput></screen>
>+<para>
> and then you can edit the file in your Emacs!<footnote><para>Many
> Emacs users set their <systemitem
> class=environvar>EDITOR</systemitem> environment to
>@@ -1431,11 +1529,10 @@
> to edit a file.</para></footnote></para></listitem>
> 
> </itemizedlist>
>-</para>
>   
> <example>
> <title>A sample <filename>.emacs</filename> file</title>
>-<screen>;; -*-Emacs-Lisp-*-
>+<programlisting>;; -*-Emacs-Lisp-*-
> 
> ;; This file is designed to be re-evaled; use the variable first-time
> ;; to avoid any problems with this.
>@@ -1509,9 +1606,9 @@
> (autoload 'ediff-buffers "ediff" "Intelligent Emacs interface to diff" t)
> (autoload 'ediff-files "ediff" "Intelligent Emacs interface to diff" t)
> (autoload 'ediff-files-remote "ediff"
>-  "Intelligent Emacs interface to diff") </screen>
>+  "Intelligent Emacs interface to diff")
> 
>-<screen>(if first-time
>+(if first-time
>     (setq auto-mode-alist
> 	  (append '(("\\.cpp$" . c++-mode)
> 		    ("\\.hpp$" . c++-mode)
>@@ -1613,9 +1710,9 @@
> (defun previous-error (n)
>   "Visit previous compilation error message and corresponding source code."
>   (interactive "p")
>-  (next-error (- n)))</screen>
>+  (next-error (- n)))
> 
>-<screen>;; Misc...
>+;; Misc...
> (transient-mark-mode 1)
> (setq mark-even-if-inactive t)
> (setq visible-bell nil)
>@@ -1716,7 +1813,7 @@
> 
> ;; All done
> (message "All done, %s%s" (user-login-name) ".")
>-</screen>
>+</programlisting>
> </example>
>   
> </sect2>
>@@ -1735,16 +1832,20 @@
> usually end in <filename>.el</filename>, short for <quote>Emacs
> Lisp</quote>. For example, if whizbang is a FreeBSD
> port, we can locate these files by doing
>-<screen>$ <userinput>find /usr/ports/lang/whizbang -name "*.el" -print</userinput></screen>
>+</para>
>+<screen>&prompt.user; <userinput>find /usr/ports/lang/whizbang -name "*.el" -print</userinput></screen>
>+<para>
> and install them by copying them into the Emacs site Lisp directory. On
> FreeBSD 2.1.0-RELEASE, this is
> <filename>/usr/local/share/emacs/site-lisp</filename>.</para>
> 
> <para>So for example, if the output from the find command was
>+</para>
> <screen>/usr/ports/lang/whizbang/work/misc/whizbang.el</screen>
>+<para>
> we would do
>-<screen>$ <userinput>cp /usr/ports/lang/whizbang/work/misc/whizbang.el /usr/local/share/emacs/site-lisp</userinput></screen>
> </para>
>+<screen>&prompt.root; <userinput>cp /usr/ports/lang/whizbang/work/misc/whizbang.el /usr/local/share/emacs/site-lisp</userinput></screen>
>   
> <para>Next, we need to decide what extension whizbang source files
> have. Let's say for the sake of argument that they all end in
>@@ -1755,11 +1856,13 @@
> <para>Find the <symbol>auto-mode-alist entry</symbol> in
> <filename>.emacs</filename> and add a line for whizbang, such
> as:
>+</para>
> <programlisting><lineannotation>&hellip;</>
> ("\\.lsp$" . lisp-mode)
> ("\\.wiz$" . whizbang-mode)
> ("\\.scm$" . scheme-mode)
> <lineannotation>&hellip;</></programlisting>  
>+<para>
> This means that Emacs will automatically go into
> <function>whizbang-mode</function> when you edit a file ending in
> <filename>.wiz</filename>.</para>
>@@ -1767,10 +1870,12 @@
> <para>Just below this, you'll find the
> <symbol>font-lock-auto-mode-list</symbol> entry. Add
> <function>whizbang-mode</function> to it like so:
>+</para>
> <programlisting>;; Auto font lock mode
> (defvar font-lock-auto-mode-list 
>   (list 'c-mode 'c++-mode 'c++-c-mode 'emacs-lisp-mode 'whizbang-mode 'lisp-mode 'perl-mode 'scheme-mode)
>   "List of modes to always start in font-lock-mode")</programlisting>
>+<para>
> This means that Emacs will always enable
> <function>font-lock-mode</function> (ie syntax highlighting) when
> editing a <filename>.wiz</filename> file.</para>

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Attachments on bug 14237: 6195