diff --git a/mach/minixST/libsys/head_em.s b/mach/minixST/libsys/head_em.s
index a771de84a..311ba8f30 100644
--- a/mach/minixST/libsys/head_em.s
+++ b/mach/minixST/libsys/head_em.s
@@ -1,5 +1,5 @@
 .define .lino,.filn
-.define EXIT
+.define EXIT,WRITE,BRK
 .define	begtext,begdata,begbss
 .define	EARRAY,ERANGE,ESET,EIDIVZ,EHEAP,EILLINS,ECASE,EBADGTO
 .define	hol0,.reghp,.limhp,.trpim,.trppc
@@ -44,6 +44,10 @@ EXIT:
 	jsr	__exit
 L0:	bra	L0
 
+BRK:	jmp	__brk
+
+WRITE:	jmp	__write
+
 	.sect .data
 begdata:
 hol0: