Add more explanation of how data_files is used (esp. where the files end up
in the installation and how that location is determined).
diff --git a/Doc/dist/dist.tex b/Doc/dist/dist.tex
index 3dfdf7d..b06d88a 100644
--- a/Doc/dist/dist.tex
+++ b/Doc/dist/dist.tex
@@ -632,8 +632,8 @@
files needed by the module distribution: configuration files,
data files, anything which does not fit in the previous categories.
-\option{data\_files} specify a sequence of \code{(directory, files)}
-pairs in the following way:
+\option{data\_files} specifies a sequence of (\var{directory},
+\var{files}) pairs in the following way:
\begin{verbatim}
setup(...
@@ -644,6 +644,17 @@
Note that you can specify the directory names where the data files
will be installed, but you cannot rename the data files themselves.
+Each (\var{directory}, \var{files}) pair in the sequence specifies the
+installation directory and the files to install there. If
+\var{directory} is a relative path, it is interpreted relative to the
+installation prefix (Python's \code{sys.prefix} for pure-Python
+packages, \code{sys.exec_prefix} for packages that contain extension
+modules). Each file name in \var{files} is interpreted relative to
+the \file{setup.py} script at the top of the package source
+distribution. No directory information from \var{files} is used to
+determine the final location of the installed file; only the name of
+the file is used.
+
You can specify the \option{data\_files} options as a simple sequence
of files without specifying a target directory, but this is not recommended,
and the \command{install} command will print a warning in this case.