Fork channel

Create a new channel as a copy of main.

Rename channel

Rename main to:

Delete channel

Delete main? This cannot be undone.

error-no-input-file.test
## This test checks the error message displayed if
## an input file does not exist.

# RUN: not llvm-dwarfutil not-existed not-existed 2>&1 | FileCheck %s -DMSG=%errc_ENOENT

# CHECK: error: 'not-existed': [[MSG]]