diff --git a/plan9/mkerrors.sh b/plan9/mkerrors.sh
index 052c86d9..85309c4a 100755
--- a/plan9/mkerrors.sh
+++ b/plan9/mkerrors.sh
@@ -140,7 +140,7 @@ echo '#include <signal.h>' | $CC -x c - -E -dM $ccflags |
 	sort >_signal.grep
 
 echo '// mkerrors.sh' "$@"
-echo '// MACHINE GENERATED BY THE COMMAND ABOVE; DO NOT EDIT'
+echo '// Code generated by the command above; DO NOT EDIT.'
 echo
 go tool cgo -godefs -- "$@" _const.go >_error.out
 cat _error.out | grep -vf _error.grep | grep -vf _signal.grep
diff --git a/plan9/mksyscall.pl b/plan9/mksyscall.pl
index ce8e1e4f..252e89e1 100755
--- a/plan9/mksyscall.pl
+++ b/plan9/mksyscall.pl
@@ -308,7 +308,7 @@ if($errors) {
 
 print <<EOF;
 // $cmdline
-// MACHINE GENERATED BY THE COMMAND ABOVE; DO NOT EDIT
+// Code generated by the command above; DO NOT EDIT.
 
 package plan9
 
diff --git a/plan9/zsyscall_plan9_386.go b/plan9/zsyscall_plan9_386.go
index b35598ad..78d8465e 100644
--- a/plan9/zsyscall_plan9_386.go
+++ b/plan9/zsyscall_plan9_386.go
@@ -1,5 +1,5 @@
 // mksyscall.pl -l32 -plan9 syscall_plan9.go
-// MACHINE GENERATED BY THE COMMAND ABOVE; DO NOT EDIT
+// Code generated by the command above; DO NOT EDIT.
 
 package plan9
 
diff --git a/plan9/zsyscall_plan9_amd64.go b/plan9/zsyscall_plan9_amd64.go
index b35598ad..78d8465e 100644
--- a/plan9/zsyscall_plan9_amd64.go
+++ b/plan9/zsyscall_plan9_amd64.go
@@ -1,5 +1,5 @@
 // mksyscall.pl -l32 -plan9 syscall_plan9.go
-// MACHINE GENERATED BY THE COMMAND ABOVE; DO NOT EDIT
+// Code generated by the command above; DO NOT EDIT.
 
 package plan9
 
diff --git a/plan9/zsyscall_plan9_arm.go b/plan9/zsyscall_plan9_arm.go
index 8dd87239..4ff9e23d 100644
--- a/plan9/zsyscall_plan9_arm.go
+++ b/plan9/zsyscall_plan9_arm.go
@@ -1,5 +1,5 @@
 // mksyscall.pl -l32 -plan9 -tags plan9,arm syscall_plan9.go
-// MACHINE GENERATED BY THE COMMAND ABOVE; DO NOT EDIT
+// Code generated by the command above; DO NOT EDIT.
 
 // +build plan9,arm