+ </refsect1>
+ <refsect1>
+ <title>Examples</title>
+ <para>
+ <programlisting>
+(def-function ("getenv" c-getenv)
+ ((name :cstring))
+ :returning :cstring)
+
+(defun getenv (key)
+ "Returns an environment variable, or NIL if it does not exist"
+ (check-type key string)
+ (with-cstring (key-cstring key)
+ (convert-from-cstring (c-getenv key-cstring))))
+ </programlisting>
+ </para>
+ </refsect1>
+ <refsect1>
+ <title>Side Effects</title>
+ <para>None.</para>
+ </refsect1>
+ <refsect1>
+ <title>Affected by</title>
+ <para>None.</para>
+ </refsect1>
+ <refsect1>
+ <title>Exceptional Situations</title>
+ <para>None.</para>
+ </refsect1>
+ </refentry>
+
+
+ <refentry id="convert-from-foreign-string">
+ <refnamediv>
+ <refname>convert-from-foreign-string</refname>
+ <refpurpose>Converts a foreign string into a Lisp string.
+ </refpurpose>
+ <refclass>Macro</refclass>
+ </refnamediv>
+ <refsynopsisdiv>
+ <title>Syntax</title>
+ <synopsis>
+ <function>convert-from-foreign-string</function> <replaceable>foreign-string &key length null-terminated-p</replaceable> => <returnvalue>string</returnvalue>
+ </synopsis>
+ </refsynopsisdiv>
+ <refsect1>
+ <title>Arguments and Values</title>
+ <variablelist>
+ <varlistentry>
+ <term><parameter>foreign-string</parameter></term>
+ <listitem>
+ <para>A foreign string.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><parameter>length</parameter></term>
+ <listitem>
+ <para>The length of the foreign string to
+convert. The default is the length of the string until a &null;
+character is reached.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><parameter>null-terminated-p</parameter></term>
+ <listitem>
+ <para>A boolean flag with a default value of &t; When true,
+the string is converted until the first &null; character is reached.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><returnvalue>string</returnvalue></term>
+ <listitem>
+ <para>A Lisp string.
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect1>
+ <refsect1>
+ <title>Description</title>