diff --git a/sys/src/cmd/syscall/mkfile b/sys/src/cmd/syscall/mkfile
index 18985a0ec..73af87d0b 100644
--- a/sys/src/cmd/syscall/mkfile
+++ b/sys/src/cmd/syscall/mkfile
@@ -16,25 +16,8 @@ UPDATE=\
 
 SYSCALL=/sys/src/libc/9syscall/sys.h
 
-tab.h:	$SYSCALL
-	awk '
-	BEGIN{ print "enum{" }
-	{ printf "%s, ", $2 }
-	END{
-		print "READ, WRITE, NTAB"
-		print "};"
-	}' <$SYSCALL >$target 
-	awk '
-	BEGIN{ print "struct Call tab[] = {" }
-	{ printf "[%s] \"%s\", (int(*)(...))%s,\n",
-		$2, tolower($2), tolower($2)
-	}
-	END{
-		print "[READ] \"read\", (int(*)(...))read,"
-		print "[WRITE] \"write\", (int(*)(...))write,"
-		print "[NTAB] nil, 0"
-		print "};"
-	}' <$SYSCALL >>$target
+tab.h:	$SYSCALL mktab.awk
+	mktab.awk $SYSCALL >$target
 
 clean:V:
 	rm -f *.[$OS] [$OS].out $TARG $HFILES
diff --git a/sys/src/cmd/syscall/mktab.awk b/sys/src/cmd/syscall/mktab.awk
new file mode 100755
index 000000000..ab8708022
--- /dev/null
+++ b/sys/src/cmd/syscall/mktab.awk
@@ -0,0 +1,14 @@
+#!/bin/awk -f
+{	e = e $2 ", "
+	s = s sprintf("[%s] \"%s\", (int(*)(...))%s,\n",
+		$2, tolower($2), tolower($2))
+}
+END{
+	e = e "READ, WRITE, NTAB"
+	s = s "[READ] \"read\", (int(*)(...))read,\n"
+	s = s "[WRITE] \"write\", (int(*)(...))write,\n"
+	s = s "[NTAB] nil, 0\n"
+	
+	print "enum{", e, "};"
+	print "struct Call tab[] = {\n", s, "};"
+}