typos, layout and other small things
diff --git a/Doc/lib/libthread.tex b/Doc/lib/libthread.tex
index bd81d7c..f745384 100644
--- a/Doc/lib/libthread.tex
+++ b/Doc/lib/libthread.tex
@@ -58,7 +58,7 @@
Lock objects have the following methods:
\renewcommand{\indexsubitem}{(lock method)}
-\begin{funcdesc}{acquire}{waitflag}
+\begin{funcdesc}{acquire}{\optional{waitflag}}
Without the optional argument, this method acquires the lock
unconditionally, if necessary waiting until it is released by another
thread (only one thread at a time can acquire a lock --- that's their