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<TD class=v2 vAlign=top><A class=v1
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in a Nutshell</A><BR>By Yukihiro Matsumoto<BR></TD></TR>
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<TD class=t1 vAlign=bottom>Chapter 2. Language
Basics</TD></TR></TBODY></TABLE>
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<H3 class=docSection1Title>2.2 Environment Variables</H3><A
name=IXT-2-126849></A><A name=IXT-2-126850></A>
<P class=docText><A name=IXT-2-126851></A>In addition to using
arguments and options on the command line, the Ruby
interpreter uses the following environment variables to
control its behavior. The <TT>ENV</TT> object contains a list
of current environment variables. </P><A
name=IXT-2-126852></A><A name=IXT-2-126853></A><A
name=IXT-2-126854></A><A name=IXT-2-126855></A><A
name=IXT-2-126856></A><A name=IXT-2-126857></A><A
name=IXT-2-126858></A><A name=IXT-2-126859></A><A
name=IXT-2-126860></A><A name=IXT-2-126861></A><A
name=IXT-2-126862></A><A name=IXT-2-126863></A><A
name=IXT-2-126864></A><A name=IXT-2-126865></A><A
name=IXT-2-126866></A><A name=IXT-2-126867></A><A
name=IXT-2-126868></A><A name=IXT-2-126869></A><A
name=IXT-2-126870></A><A name=IXT-2-126871></A><A
name=IXT-2-126872></A><A name=IXT-2-126873></A><A
name=IXT-2-126874></A><A name=IXT-2-126875></A>
<DL class=docList><A name=IXT-2-126852></A>
<DT><SPAN class=docPubcolor><SPAN class=docPubcolor><SPAN
class=docMonofont>DLN_LIBRARY_PATH</SPAN></SPAN></SPAN>
<DD>
<P class=docList><A name=IXT-2-126853></A>Search path for
dynamically loaded modules. </P><A name=IXT-2-126854></A>
<DT><SPAN class=docPubcolor><SPAN class=docPubcolor><SPAN
class=docMonofont>HOME</SPAN></SPAN></SPAN>
<DD>
<P class=docList><A name=IXT-2-126855></A>Directory moved to
when no argument is passed to <TT>Dir::chdir</TT>. Also used
by <TT>File::expand_path</TT> to expand "~". </P><A
name=IXT-2-126856></A>
<DT><SPAN class=docPubcolor><SPAN class=docPubcolor><SPAN
class=docMonofont>LOGDIR</SPAN></SPAN></SPAN>
<DD>
<P class=docList><A name=IXT-2-126857></A>Directory moved to
when no arguments are passed to <TT>Dir::chdir</TT> and
environment variable <TT>HOME</TT> isn't set. </P><A
name=IXT-2-126858></A>
<DT><SPAN class=docPubcolor><SPAN class=docPubcolor><SPAN
class=docMonofont>PATH</SPAN></SPAN></SPAN>
<DD>
<P class=docList><A name=IXT-2-126859></A><A
name=IXT-2-126860></A><A name=IXT-2-126861></A>Search path
for executing subprocesses and searching for Ruby programs
with the <TT>-S</TT> option. Separate each path with a colon
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