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<head><title>isOpen -- whether a file or database is open</title>
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<div><h1>isOpen -- whether a file or database is open</h1>
<div class="single"><h2>Synopsis</h2>
<ul><li><div class="list"><dl class="element"><dt class="heading">Usage: </dt><dd class="value"><div><tt>isOpen f</tt></div>
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<li><div class="single">Inputs:<ul><li><span><tt>f</tt>, <span>a <a href="___File.html">file</a></span> or <span>a <a href="___Database.html">database</a></span></span></li>
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<li><div class="single">Outputs:<ul><li><span><span>a <a href="___Boolean.html">Boolean value</a></span>, whether <tt>f</tt> is an open file or open database</span></li>
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<div class="single"><h2>Description</h2>
<div><p>An open file is either an input file, an output file, an input output file, or a listener.</p>
<table class="examples"><tr><td><pre>i1 : f = "test-file" << "hi there"
o1 = test-file
o1 : File</pre>
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<tr><td><pre>i2 : isOpen f
o2 = true</pre>
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<tr><td><pre>i3 : close f
o3 = test-file
o3 : File</pre>
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<tr><td><pre>i4 : isOpen f
o4 = false</pre>
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<tr><td><pre>i5 : get "test-file"
o5 = hi there</pre>
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<tr><td><pre>i6 : removeFile "test-file"</pre>
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<div class="single"><h2>See also</h2>
<ul><li><span><a href="_open__In_lp__String_rp.html" title="open an output file">openIn</a> -- open an output file</span></li>
<li><span><a href="_open__In__Out.html" title="open an input output file">openInOut</a> -- open an input output file</span></li>
<li><span><a href="_open__Listener_lp__String_rp.html" title="open a port for listening">openListener</a> -- open a port for listening</span></li>
<li><span><a href="_close.html" title="close a file">close</a> -- close a file</span></li>
<li><span><a href="_get.html" title="get the contents of a file">get</a> -- get the contents of a file</span></li>
<li><span><a href="_remove__File.html" title="remove a file">removeFile</a> -- remove a file</span></li>
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<div class="waystouse"><h2>Ways to use <tt>isOpen</tt> :</h2>
<ul><li>isOpen(Database)</li>
<li>isOpen(File)</li>
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