sergiotarxz/nuttx
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

NSH: Add support for while-do-done and until-do-done loops

Browse Source
This commit is contained in:
Gregory Nutt 2014-01-17 15:56:32 -06:00
parent f656bb59f6
commit 57ad71d6c3
1 changed files with 36 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

45
Documentation/NuttShell.html
View File

@ -8,7 +8,7 @@
<tr align="center" bgcolor="#e4e4e4">
<td>
<h1><big><font color="#3c34ec"><i>NuttShell (NSH)</i></font></big></h1>
<p>Last Updated: January 10, 2014</p>
<p>Last Updated: January 17, 2014</p>
</td>
</tr>
</table>
@ -52,25 +52,31 @@
<tr>
<td><br></td>
<td>
<a href="#builtinvars">1.4 Built-In Variables</a>
<a href="#looping">1.4 Looping</a>
</td>
</tr>
<tr>
<td><br></td>
<td>
<a href="#currentwd">1.5 Current Working Directory</a>
<a href="#builtinvars">1.5 Built-In Variables</a>
</td>
</tr>
<tr>
<td><br></td>
<td>
<a href="#environvars">1.6 Environment Variables</a>
<a href="#currentwd">1.6 Current Working Directory</a>
</td>
</tr>
<tr>
<td><br></td>
<td>
<a href="#startupscript">1.7 NSH Start-Up Script</a>
<a href="#environvars">1.7 Environment Variables</a>
</td>
</tr>
<tr>
<td><br></td>
<td>
<a href="#startupscript">1.8 NSH Start-Up Script</a>
</td>
</tr>
@ -605,7 +611,28 @@ fi
<table width ="100%">
<tr bgcolor="#e4e4e4">
<td>
<a name="builtinvars"><h2>1.4 Built-In Variables</h2></a>
<a name="looping"><h2>1.4 Looping</h2></a>
</td>
</tr>
</table>
<p>
<code>while-do-done</code> and <code>until-do-done</code> looping constructs are also supported.
These works from the command line but are primarily intended for use within NSH scripts
(see the <a href="#cmdsh"><code>sh</code></a> command).
The syntax is as follows:
</p>
<ul><dl>
<dt><code>while &lt;test-cmd&gt;; do &lt;cmd-sequence&gt;; done</code></dt>
<dd>Execute <code>&lt;cmd-sequence&gt;</code> as long as <code>&lt;test-cmd&gt;</code> has an exit status of zero.</dd>
<dt><code>until &lt;test-cmd&gt;; do &lt;cmd-sequence&gt;; done</code></dt>
<dd>Execute <code>&lt;cmd-sequence&gt;</code> as long as <code>&lt;test-cmd&gt;</code> has a non-zero exit status.</dd>
</dl></ul>
<table width ="100%">
<tr bgcolor="#e4e4e4">
<td>
<a name="builtinvars"><h2>1.5 Built-In Variables</h2></a>
</td>
</tr>
</table>
@ -623,7 +650,7 @@ fi
<table width ="100%">
<tr bgcolor="#e4e4e4">
<td>
<a name="currentwd"><h2>1.5 Current Working Directory</h2></a>
<a name="currentwd"><h2>1.6 Current Working Directory</h2></a>
</td>
</tr>
</table>
@ -641,7 +668,7 @@ fi
<table width ="100%">
<tr bgcolor="#e4e4e4">
<td>
<a name="environvars"><h2>1.6 Environment Variables</h2></a>
<a name="environvars"><h2>1.7 Environment Variables</h2></a>
</td>
</tr>
</table>
@ -661,7 +688,7 @@ fi
<table width ="100%">
<tr bgcolor="#e4e4e4">
<td>
<a name="startupscript"><h2>1.7 NSH Start-Up Script</h2></a>
<a name="startupscript"><h2>1.8 NSH Start-Up Script</h2></a>
</td>
</tr>
</table>