83 lines
2.7 KiB
HTML
83 lines
2.7 KiB
HTML
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-->
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<html>
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<head>
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<title>getenv</title>
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<link rel="stylesheet" type="text/css" media="all" href="../man.css">
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</head>
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<body bgcolor=#ffffff>
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<h2 align=center>getenv</h2>
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<h4 align=center>OS/161 Reference Manual</h4>
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<h3>Name</h3>
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<p>
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getenv - retrieve an environment variable
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</p>
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<h3>Library</h3>
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<p>
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Standard C Library (libc, -lc)
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</p>
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<h3>Synopsis</h3>
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<p>
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<tt>#include <stdlib.h></tt><br>
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<br>
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<tt>char *</tt><br>
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<tt>getenv(const char *</tt><em>variable</em><tt>);</tt>
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</p>
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<h3>Description</h3>
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<p>
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<tt>getenv</tt> retrieves the value of the environment variable
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<em>variable</em> from the current process environment.
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Unless you implement <tt>execve</tt> and environment variable passing,
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the environment used is a default environment compiled into libc.
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</p>
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<h3>Return Values</h3>
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<p>
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On success, <tt>getenv</tt> returns a pointer to the value of the
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requested variable.
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This pointer points to internal storage and the contents should not be
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modified.
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The contents will in turn be stable until/unless the process
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environment is modified.
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If the requested variable is not found, <tt>getenv</tt> returns
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<tt>NULL</tt>.
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</p>
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<h3>See Also</h3>
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<p>
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<A HREF=execvp.html>execvp</A>
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</p>
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</body>
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</html>
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