Consistently use \POSIX{} to denote POSIX. There were at least two different
ways to do it previously (not counting module names).
diff --git a/Doc/lib/libamoeba.tex b/Doc/lib/libamoeba.tex
index 1f7015f..747c5f3 100644
--- a/Doc/lib/libamoeba.tex
+++ b/Doc/lib/libamoeba.tex
@@ -119,7 +119,7 @@
\end{funcdesc}
\begin{funcdesc}{tod_gettime}{}
-Returns the time (in seconds since the Epoch, in UCT, as for POSIX) from
+Returns the time (in seconds since the Epoch, in UCT, as for \POSIX{}) from
a time server.
\end{funcdesc}