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diff --git a/docsrc/xlisp/xlisp-doc/reference/open.htm b/docsrc/xlisp/xlisp-doc/reference/open.htm new file mode 100644 index 0000000..fe2a925 --- /dev/null +++ b/docsrc/xlisp/xlisp-doc/reference/open.htm @@ -0,0 +1,117 @@ +<html><head><title>XLISP open</title>
+
+<link rel="stylesheet" type="text/css" href="reference.css">
+
+</head>
+
+<body>
+
+<a href="../start.htm">Nyquist / XLISP 2.0</a> -
+<a href="../manual/contents.htm">Contents</a> |
+<a href="../tutorials/tutorials.htm">Tutorials</a> |
+<a href="../examples/examples.htm">Examples</a> |
+<a href="reference-index.htm">Reference</a>
+
+<hr>
+
+<h1>open</h1>
+
+<hr>
+
+<p><table cellpadding="0" cellspacing="0" style="margin-left:10px"><tbody>
+<tr valign="top">
+ <td><nobr>Type:</nobr></td>
+ <td><nobr> - </nobr></td>
+ <td width="100%"><nobr>function (subr)</nobr></td>
+</tr>
+<tr valign="top">
+ <td><nobr>Source:</nobr></td>
+ <td><nobr> - </nobr></td>
+ <td width="100%"><nobr>xlfio.c</nobr></td>
+</tr>
+</tbody></table></p>
+
+<h2>Syntax</h2>
+
+<dl>
+<dt>(open <i>file</i> [:direction <i>in-out</i>])</dt>
+<dd><i>file</i> - a string expression or symbol<br>
+<i>in-out</i> - an optional keyword symbol that must be either ':input' or
+':output'. The default is ':input'.<br>
+returns - a stream</dd>
+</dl>
+
+<h2>Description</h2>
+
+<p>The 'open' function opens the 'file' for input or output. The 'file' may
+be a string expression or a symbol. Following the 'file', there is an
+optional keyword, ':direction'. The argument following this is either
+':input' or ':output' which specifies the direction of the file. If no
+':direction' is specified, the default is ':input'. When 'file' is a string,
+you may specify a complete file location or extensions like
+"/usr/local/bin/myfile.lsp" or "A:\LISP\TIM.BAT". If
+the file open was successful, then a file pointer of the following form is
+returned as the result:</p>
+
+<pre class="example">
+#<File: #99999>
+</pre>
+
+<p>If the file open was not successful, a
+<a href="nil.htm">NIL</a> is returned. For an input file, the
+file has to exist, or an error will be signaled.</p>
+
+<h2>Examples</h2>
+
+<pre class="example">
+(setq f (open 'mine :direction :output)) <font color="#008844">; create file named MINE</font>
+(print "hi" f) <font color="#008844">; returns "hi"</font>
+(close f) <font color="#008844">; file contains "hi" <newline></font>
+(setq f (open 'mine :direction :input)) <font color="#008844">; open MYFILE for input</font>
+(read f) <font color="#008844">; returns "hi"</font>
+(close f) <font color="#008844">; close it</font>
+</pre>
+
+<p><b>File names:</b> In the PC and DOS world, all file names and extensions
+["foo.bat"] are automatically made uppercase. In using XLISP, this
+means you don't have to worry about whether the name is "foo.bat",
+"FOO.BAT" or even "FoO.bAt", they will all work.
+However, in other file systems [UNIX in particular], uppercase and lowercase
+do make a difference:</p>
+
+<p>This will create a file named FOO-FILE in UNIX, because XLISP uppercases
+its symbols:</p>
+
+<pre class="example">
+(open 'foo-file :direction :output)
+</pre>
+
+<p>This will create a file named 'foo-file' because UNIX doesn't
+uppercase its file names:</p>
+
+<pre class="example">
+(open "foo-file" :direction :output)
+</pre>
+
+<p>So, if you are having trouble with opening and accessing files, check to
+make sure the file name is in the proper case.</p>
+
+<p><b>Common Lisp:</b> Common Lisp supports bidirectional files. So, porting
+Common Lisp code may be difficult to port if it uses these other file
+types.</p>
+
+<p>See the
+<a href="../manual/xlisp-man-029.htm#open">open</a>
+function in the <nobr>XLISP 2.0</nobr> manual.</p>
+
+<p><nobr> <a href="#top">Back to Top</nobr></a></p>
+
+<hr>
+
+<a href="../start.htm">Nyquist / XLISP 2.0</a> -
+<a href="../manual/contents.htm">Contents</a> |
+<a href="../tutorials/tutorials.htm">Tutorials</a> |
+<a href="../examples/examples.htm">Examples</a> |
+<a href="reference-index.htm">Reference</a>
+
+</body></html>
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