Document set [{+|-}{e|x|xe|ex}] [<name> <value>]

Documentation/NuttShell.html

@@ -8,7 +8,7 @@
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     <td>
       <h1><big><font color="#3c34ec"><i>NuttShell (NSH)</i></font></big></h1>
-      <p>Last Updated: February 5, 2017</p>
+      <p>Last Updated: April 5, 2017</p>
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@@ -2708,11 +2708,13 @@ nsh&gt;
 
 <p><b>Command Syntax:</b></p>
 <ul><pre>
-set &lt;name&gt; &lt;value&gt;
+set [{+|-}{e|x|xe|ex}] [&lt;name&gt; &lt;value&gt;]
 </pre></ul>
 <p>
   <b>Synopsis</b>.
-  Set the environment variable <code>&lt;name&gt;</code> to the string <code>&lt;value&gt;</code>.
+  Set the environment variable <code>&lt;name&gt;</code> to the string <code>&lt;value&gt;</code> and or set NSH
+  parser control options. For example,
+
   For example,
 </p>
 <ul><pre>
@@ -2724,6 +2726,51 @@ foovalue
 nsh&gt;
 </pre></ul>
 
+<p>
+    Set the 'exit on error control' and/or 'print a trace' of commands when parsing
+    scripts in NSH.  The settinngs are in effect from the point of exection, until
+    they are changed again, or in the case of the init script, the settings are
+    returned to the default settings when it exits. Included child scripts will run
+    with the parents settings and changes made in the child script will effect the
+    parent on return.
+</p>
+<p>
+    Use 'set -e' to enable and 'set +e' to disable (ignore) the exit condition on commands.
+    The default is -e. Errors cause script to exit.
+</p>
+<p>
+    Use 'set -x' to enable and 'set +x' to disable (silence) printing a trace of the script
+    commands as they are ececuted.
+    The default is +x. No printing of a trace of script commands as they are executed.
+
+</p>
+
+  Example 1 - no exit on command not found
+<ul><pre>
+    set +e
+    notacommand
+</pre></ul>
+
+  Example 2 - will exit on command not found
+<ul><pre>
+    set -e
+    notacommand
+</pre></ul>
+
+  Example 3 - will exit on command not found, and print a trace of the script commmands
+<ul><pre>
+    set -ex
+</pre></ul>
+
+  Example 4 - will exit on command not found, and print a trace of the script commmands
+              and set foobar to foovalue.
+<ul><pre>
+    set -ex foobar foovalue
+    nsh> echo $foobar
+    foovalue
+</pre></ul>
+
+
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