Fork channel

Create a new channel as a copy of main.

Rename channel

Rename main to:

Delete channel

Delete main? This cannot be undone.

zos-driver-defaults.c
// RUN: %clang -### --target=s390x-none-zos -fsyntax-only %s 2>&1 | FileCheck --check-prefix=CHECK-SHORT-ENUMS %s
// RUN: %clang -### --target=s390x-none-zos -fno-short-enums -fsyntax-only %s 2>&1 | FileCheck %s

//CHECK-SHORT-ENUMS: -fshort-enums
//CHECK-SHORT-ENUMS: -fno-signed-char

//CHECK-NOT: -fshort-enums
//CHECK: -fno-signed-char