diff --git a/cde/programs/dtksh/ksh93/src/lib/libast/include/sfio.h b/cde/programs/dtksh/ksh93/src/lib/libast/include/sfio.h
index 9f99cc3dd..52394bda2 100644
--- a/cde/programs/dtksh/ksh93/src/lib/libast/include/sfio.h
+++ b/cde/programs/dtksh/ksh93/src/lib/libast/include/sfio.h
@@ -49,7 +49,10 @@
 #if defined(__linux__)
 /* HACK On linux prevent inclusion of __FILE.h that contains a conflicting
    definition of __FILE that we define later */
+/* GLIBC */
 # define ____FILE_defined 1
+/* MUSL */
+# define __DEFINED_FILE 1
 #endif /* linux */
 
 /*	Public header file for the safe fast io package.