diff -ur tesseract-3.00/viewer/svutil.cpp tesseract-3.00-gcc47/viewer/svutil.cpp
--- tesseract-3.00/viewer/svutil.cpp	2010-09-30 17:22:07.000000000 +0200
+++ tesseract-3.00-gcc47/viewer/svutil.cpp	2012-07-31 23:30:16.000000000 +0200
@@ -39,6 +39,7 @@
 #include <signal.h>
 #include <stdlib.h>
 #include <string.h>
+#include <unistd.h>
 #include <netdb.h>
 #include <sys/socket.h>
 #ifdef __linux__