added libsignal.tex
diff --git a/Doc/lib/lib.tex b/Doc/lib/lib.tex
index d3901b2..b7b4068 100644
--- a/Doc/lib/lib.tex
+++ b/Doc/lib/lib.tex
@@ -78,6 +78,7 @@
 \input{libppath}		% really posixpath
 \input{libpwd}
 \input{libselect}
+\input{libsignal}
 \input{libsocket}
 \input{libthread}