diff --git a/docs/cmu-user/unix.tex b/docs/cmu-user/unix.tex
index bb02ced84acf9189847303422c3789300fcda6f0..901b47685bc7604305f44b5d2fa3f792d9944eb0 100644
--- a/docs/cmu-user/unix.tex
+++ b/docs/cmu-user/unix.tex
@@ -295,6 +295,7 @@ For example, to use the \code{chdir} syscall:
 
 
 \section{File Descriptor Streams}
+\label{sec:fds}
 
 Many of the UNIX system calls return file descriptors.  Instead of using other
 UNIX system calls to perform I/O on them, you can create a stream around them.