+The
+.B dllmap
+element takes two attributes:
+.TP
+.I dll
+This should be the same string used in the DllImport attribute, optionally
+prefixed with "i:" to indicate that the string must be matched in a
+case-insensitive way
+.TP
+.I target
+This should be the name of the library where the function can be found:
+this name should be suitable for use with the platform native shared library
+loading routines (dlopen etc.), so you may want to check the manpages for that, too.
+.SH <dllentry> directive
+This directive can be used to map a specific dll/function pair to a different
+library and also a different function name. It should appear inside a
+.B dllmap
+element with only the dll attribute specified.
+.PP
+The
+.B dllentry
+element takes 3 attributes:
+.TP
+.I dll
+This is the target library, where the function can be found.
+.TP
+.I name
+This is the name of the function as it appears in the metadata: it is the name
+of the P/Invoke method.
+.TP
+.I target
+This is the name of the function to lookup instead of the name specified in the
+P/Invoke method.
+.SH Mapping based on operating system and cpu
+Both the
+.B dllmap
+and the
+.B dllentry
+elements allow the following two attributes which make it easy to use a single
+configuration file and support multiple operating systems and architectures with
+different mapping requirements:
+.TP
+.I os
+This is the name of the operating system for which the mapping should be applied.
+Allowed values are: linux, osx, solaris, freebsd, openbsd, netbsd, windows, aix, hpux.
+.TP
+.I cpu
+This is the name of the architecture for which the mapping should be applied.
+Allowed values are: x86, x86-64, sparc, ppc, s390, s390x, arm, mips,
+alpha, hppa, ia64.
+.TP
+.I wordsize
+This is the size of registers on the target architecture, it can be
+either 32 or 64.
+.PP
+The attribute value for both attributes can be a comma-separated list of the allowed
+values. Additionally, the first character may be a
+.I '!'
+to reverse the meaning. An attribute value of "!windows,osx", for example, would mean
+that the entry is considered on all operating systems, except on Windows and OS X.
+No spaces are allowed in any part of the value.
+.PP
+Note that later entries will override the entries defined earlier in the file.