Clarify docs about os.popen[234].
diff --git a/Doc/lib/libos.tex b/Doc/lib/libos.tex
index 2d0327f..517bddc 100644
--- a/Doc/lib/libos.tex
+++ b/Doc/lib/libos.tex
@@ -354,7 +354,7 @@
\end{funcdesc}
-For each of these \function{popen()} variants, if \var{bufsize} is
+For each of the following \function{popen()} variants, if \var{bufsize} is
specified, it specifies the buffer size for the I/O pipes.
\var{mode}, if provided, should be the string \code{'b'} or
\code{'t'}; on Windows this is needed to determine whether the file
@@ -366,7 +366,7 @@
intervention (as with \function{os.spawnv()}). If \var{cmd} is a string it will
be passed to the shell (as with \function{os.system()}).
-These methods do not make it possible to retrieve the return code from
+These methods do not make it possible to retrieve the exit status from
the child processes. The only way to control the input and output
streams and also retrieve the return codes is to use the
\class{Popen3} and \class{Popen4} classes from the \refmodule{popen2}