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+@node realpath
+@section @code{realpath}
+@findex realpath
+
+POSIX specification: @url{http://www.opengroup.org/susv3xsh/realpath.html}
+
+Gnulib module: ---
+
+Portability problems fixed by Gnulib:
+@itemize
+@end itemize
+
+Portability problems not fixed by Gnulib:
+@itemize
+@item
+This function is missing on some platforms:
+mingw, BeOS.
+@item
+This function does not allow to determine the required size of output buffer;
+PATH_MAX --- if it is defined --- is nothing more than a guess.
+@end itemize
+
+Extension: Gnulib provides a module @samp{canonicalize-lgpl} that defines a
+function @code{canonicalize_file_name} that is like @code{realpath} but without
+size limitations.