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When the<TT>`libltdl'</TT> subdirectory of a project is configured, the list isnarrowed to include only those <EM>mechanisms</EM>, or simply<EM>loaders</EM>, which can work on the host architecture. When<SAMP>`lt_dlopen'</SAMP> is called, the loaders in this list are tried, inorder, until the named module has loaded, or all of the loaders in thelist have been exhausted. The entries in the final list of loaders eachhave a unique name, although there may be several candidate loaders fora single name before the list is narrowed. For example, the<SAMP>`dlopen'</SAMP> loader is implemented differently on BeOS and Solaris --for a single host, there can be only one implementation of any namedloader. The name of a module loader is something entirely different tothe name of a loaded module, something that should become clearer as youread on.</P><P>In addition to the loaders supplied with libltdl, your project can addmore loaders of its own. New loaders can be added to the end of theexisting list, or immediately before any other particular loader, thusgiving you complete control of the relative priorities of all of theactive loaders in your project. </P><P>In your module loading API, you might even support the dynamicloading of user supplied loaders: that is your users would be able tocreate dynamic modules which added more loading mechanisms to theexisting list of loaders!</P><P>Version 1.4 of Libtool has a default list that potentially contains animplementation of the following loaders (assuming all are supported bythe host platform):</P><P><DL COMPACT><DT><CODE>dlpreopen</CODE><DD>If the named module was preloaded, use the preloaded symbol table forsubsequent <CODE>lt_dlsym</CODE> calls.<P><DT><CODE>dlopen</CODE><DD>If the host machine has a native dynamic loader API use that to tryand load the module.<P><DT><CODE>dld</CODE><DD>If the host machine has GNUdld<A NAME="DOCF44" HREF="autobook_fot.html#FOOT44">(44)</A>, use that to tryand load the module.</DL><P>Note that loader names with a <SAMP>`dl'</SAMP> prefix are reserved for futureuse by Libtool, so you should choose something else for your own modulenames to prevent a name clash with future Libtool releases.</P><P><A NAME="libltdl Loader Management"></A></TR></TABLE><BR> <FONT SIZE="-1">This document was generatedby <I>Gary V. Vaughan</I> on <I>September, 12 2004</I>using <A HREF="http://www.mathematik.uni-kl.de/~obachman/Texi2html"><I>texi2html</I></A></BODY></HTML>⌨️ 快捷键说明
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