diff --git a/cde/programs/dtdocbook/tcl/tclPosixStr.c b/cde/programs/dtdocbook/tcl/tclPosixStr.c
index 376defbaf..cce2c7aae 100644
--- a/cde/programs/dtdocbook/tcl/tclPosixStr.c
+++ b/cde/programs/dtdocbook/tcl/tclPosixStr.c
@@ -347,9 +347,11 @@ Tcl_ErrnoId()
 #ifdef ENOTSOCK
 	case ENOTSOCK: return "ENOTSOCK";
 #endif
+#if !defined(linux)
 #ifdef ENOTSUP
 	case ENOTSUP: return "ENOTSUP";
 #endif
+#endif
 #ifdef ENOTTY
 	case ENOTTY: return "ENOTTY";
 #endif
@@ -794,9 +796,11 @@ Tcl_ErrnoMsg(err)
 #ifdef ENOTSOCK
 	case ENOTSOCK: return "socket operation on non-socket";
 #endif
+#if !defined(linux)
 #ifdef ENOTSUP
 	case ENOTSUP: return "operation not supported";
 #endif
+#endif
 #ifdef ENOTTY
 	case ENOTTY: return "inappropriate device for ioctl";
 #endif