diff --git a/src/lib/system/openbsd/gcc/x86_64/Unix.Mod b/src/lib/system/openbsd/gcc/x86_64/Unix.Mod
index c0abebec..8f009f1f 100644
--- a/src/lib/system/openbsd/gcc/x86_64/Unix.Mod
+++ b/src/lib/system/openbsd/gcc/x86_64/Unix.Mod
@@ -229,7 +229,7 @@ from man gettimeofday
     interval*, value*: Timeval
   END ;
 
-  FdSet* = ARRAY 8 OF SET;
+  FdSet* = ARRAY 16 OF SET;
 
   SigCtxPtr* = POINTER TO SigContext;
   SigContext* = RECORD
@@ -527,3 +527,4 @@ BEGIN
    StatCheck();
 
 END Unix.
+