+The four functions with \fIn\fP as the last argument return
+a leading substring at most \fIn\fP characters long
+(exclusive of the trailing NUL).
+Transfer stops at the end of the current line, or when \fIn\fP characters have
+been stored at the location referenced by \fIwstr\fP.
+.PP
+If the size \fIn\fP is not large enough to store a complete complex character,