Update STDLIB documentation

Language cleaned up by the technical writers xsipewe and tmanevik
from Combitech. Proofreading and corrections by Björn Gustavsson
and Hans Bolinder.

1 files changed, 217 insertions, 163 deletions

diff --git a/lib/stdlib/doc/src/timer.xml b/lib/stdlib/doc/src/timer.xml
index 4f259d57a8..8f2ce36b06 100644
--- a/lib/stdlib/doc/src/timer.xml
+++ b/lib/stdlib/doc/src/timer.xml
@@ -30,26 +30,25 @@
     <checked></checked>
     <date>1998-09-09</date>
     <rev>D</rev>
-    <file>timer.sgml</file>
+    <file>timer.xml</file>
   </header>
   <module>timer</module>
-  <modulesummary>Timer Functions</modulesummary>
+  <modulesummary>Timer functions.</modulesummary>
   <description>
     <p>This module provides useful functions related to time. Unless otherwise
-      stated, time is always measured in <c>milliseconds</c>.  All
-      timer functions return immediately, regardless of work carried
-      out by another process. 
-      </p>
-    <p>Successful evaluations of the timer functions yield return values
-      containing a timer reference, denoted <c>TRef</c> below. By using 
-      <c>cancel/1</c>, the returned reference can be used to cancel any
-      requested action. A <c>TRef</c> is an Erlang term, the contents
-      of which must not be altered.
-      </p>
-    <p>The timeouts are not exact, but should be <c>at least</c> as long
-      as requested.
-      </p>
+      stated, time is always measured in <em>milliseconds</em>. All
+      timer functions return immediately, regardless of work done by another
+      process.</p>
+    <p>Successful evaluations of the timer functions give return values
+      containing a timer reference, denoted <c>TRef</c>. By using
+      <seealso marker="#cancel/1"><c>cancel/1</c></seealso>,
+      the returned reference can be used to cancel any
+      requested action. A <c>TRef</c> is an Erlang term, which contents
+      must not be changed.</p>
+    <p>The time-outs are not exact, but are <em>at least</em> as long
+      as requested.</p>
   </description>
+
   <datatypes>
     <datatype>
       <name name="time"/>
@@ -60,231 +59,286 @@
       <desc><p>A timer reference.</p></desc>
     </datatype>
   </datatypes>
+
   <funcs>
     <func>
-      <name name="start" arity="0"/>
-      <fsummary>Start a global timer server (named <c>timer_server</c>).</fsummary>
+      <name name="apply_after" arity="4"/>
+      <fsummary>Apply <c>Module:Function(Arguments)</c> after a specified
+        <c>Time</c>.</fsummary>
       <desc>
-        <p>Starts the timer server. Normally, the server does not need
-          to be started explicitly. It is started dynamically if it
-          is needed. This is useful during development, but in a
-          target system the server should be started explicitly.  Use
-          configuration parameters for <c>kernel</c> for this.</p>
+        <p>Evaluates <c>apply(<anno>Module</anno>, <anno>Function</anno>,
+          <anno>Arguments</anno>)</c> after <c><anno>Time</anno></c>
+          milliseconds.</p>
+        <p>Returns <c>{ok, <anno>TRef</anno>}</c> or
+          <c>{error, <anno>Reason</anno>}</c>.</p>
       </desc>
     </func>
+
     <func>
-      <name name="apply_after" arity="4"/>
-      <fsummary>Apply <c>Module:Function(Arguments)</c>after a  specified <c>Time</c>.</fsummary>
+      <name name="apply_interval" arity="4"/>
+      <fsummary>Evaluate <c>Module:Function(Arguments)</c> repeatedly at
+        intervals of <c>Time</c>.</fsummary>
       <desc>
-        <p>Evaluates <c>apply(<anno>Module</anno>, <anno>Function</anno>, <anno>Arguments</anno>)</c> after <c><anno>Time</anno></c> amount of time
-          has elapsed. Returns <c>{ok, <anno>TRef</anno>}</c>, or <c>{error, <anno>Reason</anno>}</c>.</p>
+        <p>Evaluates <c>apply(<anno>Module</anno>, <anno>Function</anno>,
+          <anno>Arguments</anno>)</c> repeatedly at intervals of
+          <c><anno>Time</anno></c>.</p>
+        <p>Returns <c>{ok, <anno>TRef</anno>}</c> or
+          <c>{error, <anno>Reason</anno>}</c>.</p>
       </desc>
     </func>
+
     <func>
-      <name name="send_after" arity="2"/>
-      <name name="send_after" arity="3"/>
-      <fsummary>Send <c>Message</c>to <c>Pid</c>after a specified <c>Time</c>.</fsummary>
+      <name name="cancel" arity="1"/>
+      <fsummary>Cancel a previously requested time-out identified by
+        <c>TRef</c>.</fsummary>
       <desc>
-        <taglist>
-          <tag><c>send_after/3</c></tag>
-          <item>
-            <p>Evaluates <c><anno>Pid</anno> ! <anno>Message</anno></c> after <c><anno>Time</anno></c> amount
-              of time has elapsed. (<c><anno>Pid</anno></c> can also be an atom of a
-              registered name.) Returns <c>{ok, <anno>TRef</anno>}</c>, or
-              <c>{error, <anno>Reason</anno>}</c>.</p>
-          </item>
-          <tag><c>send_after/2</c></tag>
-          <item>
-            <p>Same as <c>send_after(<anno>Time</anno>, self(), <anno>Message</anno>)</c>.</p>
-          </item>
-        </taglist>
+        <p>Cancels a previously requested time-out. <c><anno>TRef</anno></c> is
+          a unique
+          timer reference returned by the related timer function.</p>
+        <p>Returns <c>{ok, cancel}</c>, or <c>{error, <anno>Reason</anno>}</c>
+          when <c><anno>TRef</anno></c> is not a timer reference.</p>
       </desc>
     </func>
+
     <func>
-      <name name="kill_after" arity="1"/>
-      <name name="kill_after" arity="2"/>
       <name name="exit_after" arity="2"/>
       <name name="exit_after" arity="3"/>
-      <fsummary>Send an exit signal with <c>Reason</c>after a specified <c>Time</c>.</fsummary>
+      <fsummary>Send an exit signal with <c>Reason</c> after a specified
+        <c>Time</c>.</fsummary>
+      <desc>
+        <p><c>exit_after/2</c> is the same as
+          <c>exit_after(<anno>Time</anno>, self(),
+          <anno>Reason1</anno>)</c>.</p>
+        <p><c>exit_after/3</c> sends an exit signal with reason
+          <c><anno>Reason1</anno></c> to
+          pid <c><anno>Pid</anno></c>. Returns <c>{ok, <anno>TRef</anno>}</c>
+          or <c>{error, <anno>Reason2</anno>}</c>.</p>
+      </desc>
+    </func>
+
+    <func>
+      <name name="hms" arity="3"/>
+      <fsummary>Convert <c>Hours</c>+<c>Minutes</c>+<c>Seconds</c> to
+        <c>Milliseconds</c>.</fsummary>
+      <desc>
+        <p>Returns the number of milliseconds in <c><anno>Hours</anno> +
+          <anno>Minutes</anno> + <anno>Seconds</anno></c>.</p>
+      </desc>
+    </func>
+
+    <func>
+      <name name="hours" arity="1"/>
+      <fsummary>Convert <c>Hours</c> to <c>Milliseconds</c>.</fsummary>
+      <desc>
+        <p>Returns the number of milliseconds in <c><anno>Hours</anno></c>.</p>
+      </desc>
+    </func>
+
+    <func>
+      <name name="kill_after" arity="1"/>
+      <name name="kill_after" arity="2"/>
+      <fsummary>Send an exit signal with <c>Reason</c> after a specified
+        <c>Time</c>.</fsummary>
+      <desc>
+        <p><c>kill_after/1</c> is the same as
+          <c>exit_after(<anno>Time</anno>, self(), kill)</c>.</p>
+        <p><c>kill_after/2</c> is the same as
+          <c>exit_after(<anno>Time</anno>, <anno>Pid</anno>, kill)</c>.</p>
+      </desc>
+    </func>
+
+    <func>
+      <name name="minutes" arity="1"/>
+      <fsummary>Converts <c>Minutes</c> to <c>Milliseconds</c>.</fsummary>
+      <desc>
+        <p>Returns the number of milliseconds in
+          <c><anno>Minutes</anno></c>.</p>
+      </desc>
+    </func>
+
+    <func>
+      <name name="now_diff" arity="2"/>
+      <fsummary>Calculate time difference between time stamps.</fsummary>
+      <type_desc variable="Tdiff">In microseconds</type_desc>
+      <desc>
+        <p>Calculates the time difference <c><anno>Tdiff</anno> =
+          <anno>T2</anno> - <anno>T1</anno></c> in <em>microseconds</em>,
+          where <c><anno>T1</anno></c> and <c><anno>T2</anno></c>
+          are time-stamp tuples on the same format as returned from
+          <seealso marker="erts:erlang#timestamp/0">
+          <c>erlang:timestamp/0</c></seealso> or
+          <seealso marker="kernel:os#timestamp/0">
+          <c>os:timestamp/0</c></seealso>.</p>
+      </desc>
+    </func>
+
+    <func>
+      <name name="seconds" arity="1"/>
+      <fsummary>Convert <c>Seconds</c> to <c>Milliseconds</c>.</fsummary>
+      <desc>
+        <p>Returns the number of milliseconds in
+          <c><anno>Seconds</anno></c>.</p>
+      </desc>
+    </func>
+
+    <func>
+      <name name="send_after" arity="2"/>
+      <name name="send_after" arity="3"/>
+      <fsummary>Send <c>Message</c> to <c>Pid</c> after a specified
+        <c>Time</c>.</fsummary>
       <desc>
         <taglist>
-          <tag><c>exit_after/3</c></tag>
-          <item>
-            <p>Send an exit signal with reason <c><anno>Reason1</anno></c> to Pid
-              <c><anno>Pid</anno></c>. Returns <c>{ok, <anno>TRef</anno>}</c>, or
-              <c>{error, <anno>Reason2</anno>}</c>.</p>
-          </item>
-          <tag><c>exit_after/2</c></tag>
-          <item>
-            <p>Same as <c>exit_after(<anno>Time</anno>, self(), <anno>Reason1</anno>)</c>.     </p>
-          </item>
-          <tag><c>kill_after/2</c></tag>
+          <tag><c>send_after/3</c></tag>
           <item>
-            <p>Same as <c>exit_after(<anno>Time</anno>, <anno>Pid</anno>, kill)</c>.     </p>
+            <p>Evaluates <c><anno>Pid</anno> ! <anno>Message</anno></c> after
+              <c><anno>Time</anno></c> milliseconds. (<c><anno>Pid</anno></c>
+              can also be an atom of a registered name.)</p>
+            <p>Returns <c>{ok, <anno>TRef</anno>}</c> or
+              <c>{error, <anno>Reason</anno>}</c>.</p>
           </item>
-          <tag><c>kill_after/1</c></tag>
+          <tag><c>send_after/2</c></tag>
           <item>
-            <p>Same as <c>exit_after(<anno>Time</anno>, self(), kill)</c>.     </p>
+            <p>Same as <c>send_after(<anno>Time</anno>, self(),
+              <anno>Message</anno>)</c>.</p>
           </item>
         </taglist>
       </desc>
     </func>
-    <func>
-      <name name="apply_interval" arity="4"/>
-      <fsummary>Evaluate <c>Module:Function(Arguments)</c>repeatedly at  intervals of <c>Time</c>.</fsummary>
-      <desc>
-        <p>Evaluates <c>apply(<anno>Module</anno>, <anno>Function</anno>, <anno>Arguments</anno>)</c> repeatedly at
-          intervals of  <c><anno>Time</anno></c>. Returns <c>{ok, <anno>TRef</anno>}</c>, or
-          <c>{error, <anno>Reason</anno>}</c>.</p>
-      </desc>
-    </func>
+
     <func>
       <name name="send_interval" arity="2"/>
       <name name="send_interval" arity="3"/>
-      <fsummary>Send <c>Message</c>repeatedly at intervals of <c>Time</c>.</fsummary>
+      <fsummary>Send <c>Message</c> repeatedly at intervals of <c>Time</c>.
+      </fsummary>
       <desc>
         <taglist>
           <tag><c>send_interval/3</c></tag>
           <item>
-            <p>Evaluates <c><anno>Pid</anno> ! <anno>Message</anno></c> repeatedly after <c><anno>Time</anno></c>
-              amount of time has elapsed. (<c><anno>Pid</anno></c> can also be an atom of
-              a registered name.) Returns <c>{ok, <anno>TRef</anno>}</c> or
+            <p>Evaluates <c><anno>Pid</anno> ! <anno>Message</anno></c>
+              repeatedly after <c><anno>Time</anno></c> milliseconds.
+              (<c><anno>Pid</anno></c> can also be
+              an atom of a registered name.)</p>
+            <p>Returns <c>{ok, <anno>TRef</anno>}</c> or
               <c>{error, <anno>Reason</anno>}</c>.</p>
           </item>
           <tag><c>send_interval/2</c></tag>
           <item>
-            <p>Same as <c>send_interval(<anno>Time</anno>, self(), <anno>Message</anno>)</c>.</p>
+            <p>Same as <c>send_interval(<anno>Time</anno>, self(),
+              <anno>Message</anno>)</c>.</p>
           </item>
         </taglist>
       </desc>
     </func>
+
     <func>
-      <name name="cancel" arity="1"/>
-      <fsummary>Cancel a previously requested timeout identified by <c>TRef</c>.</fsummary>
+      <name name="sleep" arity="1"/>
+      <fsummary>Suspend the calling process for <c>Time</c> milliseconds.
+      </fsummary>
       <desc>
-        <p>Cancels a previously requested timeout. <c><anno>TRef</anno></c> is a unique
-          timer reference returned by the timer function in question. Returns
-          <c>{ok, cancel}</c>, or <c>{error, <anno>Reason</anno>}</c> when <c><anno>TRef</anno></c>
-          is not a timer reference.</p>
+        <p>Suspends the process calling this function for
+          <c><anno>Time</anno></c> milliseconds and then returns <c>ok</c>,
+          or suspends the process forever if <c><anno>Time</anno></c> is the
+          atom <c>infinity</c>. Naturally, this
+          function does <em>not</em> return immediately.</p>
       </desc>
     </func>
+
     <func>
-      <name name="sleep" arity="1"/>
-      <fsummary>Suspend the calling process for <c>Time</c>amount of milliseconds.</fsummary>
+      <name name="start" arity="0"/>
+      <fsummary>Start a global timer server (named <c>timer_server</c>).
+      </fsummary>
       <desc>
-        <p>Suspends the process calling this function for <c><anno>Time</anno></c> amount
-          of milliseconds and then returns <c>ok</c>, or suspend the process
-	  forever if <c><anno>Time</anno></c> is the atom <c>infinity</c>. Naturally, this
-          function does <em>not</em> return immediately.</p>
+        <p>Starts the timer server. Normally, the server does not need
+          to be started explicitly. It is started dynamically if it
+          is needed. This is useful during development, but in a
+          target system the server is to be started explicitly. Use
+          configuration parameters for
+          <seealso marker="kernel:index"><c>Kernel</c></seealso> for this.</p>
       </desc>
     </func>
+
     <func>
       <name name="tc" arity="1"/>
       <name name="tc" arity="2"/>
       <name name="tc" arity="3"/>
       <fsummary>Measure the real time it takes to evaluate <c>apply(Module,
-      Function, Arguments)</c> or <c>apply(Fun, Arguments)</c></fsummary>
+        Function, Arguments)</c> or <c>apply(Fun, Arguments)</c>.</fsummary>
       <type_desc variable="Time">In microseconds</type_desc>
       <desc>
         <taglist>
           <tag><c>tc/3</c></tag>
           <item>
-            <p>Evaluates <c>apply(<anno>Module</anno>, <anno>Function</anno>, <anno>Arguments</anno>)</c> and measures
-              the elapsed real time as reported by <c>os:timestamp/0</c>.
-              Returns <c>{<anno>Time</anno>, <anno>Value</anno>}</c>, where
-              <c><anno>Time</anno></c> is the elapsed real time in <em>microseconds</em>,
-              and <c><anno>Value</anno></c> is what is returned from the apply.</p>
+            <p>Evaluates <c>apply(<anno>Module</anno>, <anno>Function</anno>,
+              <anno>Arguments</anno>)</c> and measures the elapsed real time as 
+              reported by <seealso marker="os:timestamp/0">
+              <c>os:timestamp/0</c></seealso>.</p>
+            <p>Returns <c>{<anno>Time</anno>, <anno>Value</anno>}</c>, where
+              <c><anno>Time</anno></c> is the elapsed real time in
+              <em>microseconds</em>, and <c><anno>Value</anno></c> is what is
+              returned from the apply.</p>
           </item>
           <tag><c>tc/2</c></tag>
           <item>
-            <p>Evaluates <c>apply(<anno>Fun</anno>, <anno>Arguments</anno>)</c>. Otherwise works
-            like <c>tc/3</c>.</p>
+            <p>Evaluates <c>apply(<anno>Fun</anno>, <anno>Arguments</anno>)</c>.
+              Otherwise the same as <c>tc/3</c>.</p>
           </item>
           <tag><c>tc/1</c></tag>
           <item>
-            <p>Evaluates <c><anno>Fun</anno>()</c>. Otherwise works like <c>tc/2</c>.</p>
+            <p>Evaluates <c><anno>Fun</anno>()</c>. Otherwise the same as
+              <c>tc/2</c>.</p>
           </item>
-
         </taglist>
       </desc>
     </func>
-    <func>
-      <name name="now_diff" arity="2"/>
-      <fsummary>Calculate time difference between timestamps</fsummary>
-      <type_desc variable="Tdiff">In microseconds</type_desc>
-      <desc>
-        <p>Calculates the time difference <c><anno>Tdiff</anno> = <anno>T2</anno> - <anno>T1</anno></c> in
-        <em>microseconds</em>, where <c><anno>T1</anno></c> and <c><anno>T2</anno></c>
-        are timestamp tuples on the same format as returned from
-	<seealso marker="erts:erlang#timestamp/0"><c>erlang:timestamp/0</c></seealso>,
-	or <seealso marker="kernel:os#timestamp/0"><c>os:timestamp/0</c></seealso>.</p>
-      </desc>
-    </func>
-    <func>
-      <name name="seconds" arity="1"/>
-      <fsummary>Convert <c>Seconds</c>to <c>Milliseconds</c>.</fsummary>
-      <desc>
-        <p>Returns the number of milliseconds in <c><anno>Seconds</anno></c>.</p>
-      </desc>
-    </func>
-    <func>
-      <name name="minutes" arity="1"/>
-      <fsummary>Converts <c>Minutes</c> to <c>Milliseconds</c>.</fsummary>
-      <desc>
-        <p>Return the number of milliseconds in <c><anno>Minutes</anno></c>.</p>
-      </desc>
-    </func>
-    <func>
-      <name name="hours" arity="1"/>
-      <fsummary>Convert <c>Hours</c>to <c>Milliseconds</c>.</fsummary>
-      <desc>
-        <p>Returns the number of milliseconds in <c><anno>Hours</anno></c>.</p>
-      </desc>
-    </func>
-    <func>
-      <name name="hms" arity="3"/>
-      <fsummary>Convert <c>Hours</c>+<c>Minutes</c>+<c>Seconds</c>to <c>Milliseconds</c>.</fsummary>
-      <desc>
-        <p>Returns the number of milliseconds in <c><anno>Hours</anno> + <anno>Minutes</anno> + <anno>Seconds</anno></c>.</p>
-      </desc>
-    </func>
   </funcs>
 
   <section>
     <title>Examples</title>
-    <p>This example illustrates  how to print out "Hello World!" in 5 seconds:</p>
+    <p><em>Example 1</em></p>
+    <p>The following example shows how to print "Hello World!" in 5 seconds:</p>
     <pre>
-      1> <input>timer:apply_after(5000, io, format, ["~nHello World!~n", []]).</input>
-      {ok,TRef}
-      Hello World!</pre>
-    <p>The following coding example illustrates a process which performs a 
-      certain action and if this action is not completed within a certain 
-      limit, then the process is killed.</p>
+1> <input>timer:apply_after(5000, io, format, ["~nHello World!~n", []]).</input>
+{ok,TRef}
+Hello World!</pre>
+
+    <p><em>Example 2</em></p>
+    <p>The following example shows a process performing a 
+      certain action, and if this action is not completed within a certain 
+      limit, the process is killed:</p>
     <code type="none">
-      Pid = spawn(mod, fun, [foo, bar]),
-      %% If pid is not finished in 10 seconds, kill him
-      {ok, R} = timer:kill_after(timer:seconds(10), Pid),
-      ...
-      %% We change our mind...
-      timer:cancel(R),
-      ...</code>
+Pid = spawn(mod, fun, [foo, bar]),
+%% If pid is not finished in 10 seconds, kill him
+{ok, R} = timer:kill_after(timer:seconds(10), Pid),
+...
+%% We change our mind...
+timer:cancel(R),
+...</code>
   </section>
 
   <section>
-    <title>WARNING</title>
-    <p>A timer can always be removed by calling <c>cancel/1</c>.
-      </p>
-    <p>An interval timer, i.e. a timer created by evaluating any of the 
-      functions <c>apply_interval/4</c>, <c>send_interval/3</c>, and 
-      <c>send_interval/2</c>, is linked to the process towards which
-      the timer performs its task.
-      </p>
-    <p>A one-shot timer, i.e. a timer created by evaluating any of the
-      functions <c>apply_after/4</c>, <c>send_after/3</c>, 
-      <c>send_after/2</c>, <c>exit_after/3</c>, <c>exit_after/2</c>, 
-      <c>kill_after/2</c>, and <c>kill_after/1</c> is not linked to any
-      process. Hence, such a timer is removed only when it reaches its 
-      timeout, or if it is explicitly removed by a call to <c>cancel/1</c>.</p>
+    <title>Notes</title>
+    <p>A timer can always be removed by calling
+      <seealso marker="#cancel/1"><c>cancel/1</c></seealso>.</p>
+
+    <p>An interval timer, that is, a timer created by evaluating any of the
+      functions
+      <seealso marker="#apply_interval/4"><c>apply_interval/4</c></seealso>,
+      <seealso marker="#send_interval/3"><c>send_interval/3</c></seealso>, and
+      <seealso marker="#send_interval/2"><c>send_interval/2</c></seealso>
+      is linked to the process to which the timer performs its task.</p>
+
+    <p>A one-shot timer, that is, a timer created by evaluating any of the
+      functions
+      <seealso marker="#apply_after/4"><c>apply_after/4</c></seealso>,
+      <seealso marker="#send_after/3"><c>send_after/3</c></seealso>,
+      <seealso marker="#send_after/2"><c>send_after/2</c></seealso>,
+      <seealso marker="#exit_after/3"><c>exit_after/3</c></seealso>,
+      <seealso marker="#exit_after/2"><c>exit_after/2</c></seealso>,
+      <seealso marker="#kill_after/2"><c>kill_after/2</c></seealso>, and
+      <seealso marker="#kill_after/1"><c>kill_after/1</c></seealso>
+      is not linked to any process. Hence, such a timer is removed only
+      when it reaches its time-out, or if it is explicitly removed by a call to
+      <seealso marker="#cancel/1"><c>cancel/1</c></seealso>.</p>
   </section>
 </erlref>