\section{Environment variables}\label{envvars}
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This section describes all environment variables that affect execution of
wxWidgets programs.

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\begin{twocollist}\itemsep=0pt

\twocolitem{\tt{WXTRACE}}{(Debug build only.)
This variable can be set to a comma-separated list of trace masks used in
\helpref{wxLogTrace}{wxlogtrace} calls;
\helpref{wxLog::AddTraceMask}{wxlogaddtracemask} is called for every mask
in the list during wxWidgets initialization.}

\twocolitem{\tt{WXPREFIX}}{(Unix only.)
Overrides installation prefix. Normally, the prefix
is hard-coded and is the same as the value passed to {\tt configure} via
the {\tt --prefix} switch when compiling the library (typically
{\tt /usr/local} or {\tt /usr}). You can set WXPREFIX if you are for example
distributing a binary version of an application and you don't know in advance
where it will be installed.}

\twocolitem{\tt{WXMODE}}{(wxMGL only.)
Sets MGL video mode. The value must be in form
{\it width}x{\it height}-{\it depth}. The default is {\tt 640x480-16}.}

\twocolitem{\tt{WXSTDERR}}{(wxMGL only.)
Redirects stderr output to a file.}

\end{twocollist}