Running `dnf -y update --best` when stdin (fd 0) is not open gives this error: [. . .] Delta RPMs reduced 93.7 MB of updates to 54.7 MB (41.1% saved) warning: /var/cache/dnf/updates-e042e478e0621ea6/packages/kernel-4.2.5-300.fc23.x86_64.rpm: Header V3 RSA/SHA256 Signature, key ID 34ec9cba: NOKEY The downloaded packages were saved in cache till the next successful transaction. You can remove cached packages by executing 'dnf clean packages'. Traceback (most recent call last): File "/bin/dnf", line 35, in <module> main.user_main(sys.argv[1:], exit_code=True) File "/usr/lib/python3.4/site-packages/dnf/cli/main.py", line 198, in user_main errcode = main(args) File "/usr/lib/python3.4/site-packages/dnf/cli/main.py", line 84, in main return _main(base, args) File "/usr/lib/python3.4/site-packages/dnf/cli/main.py", line 144, in _main ret = resolving(cli, base) File "/usr/lib/python3.4/site-packages/dnf/cli/main.py", line 173, in resolving base.do_transaction(display=displays) File "/usr/lib/python3.4/site-packages/dnf/cli/cli.py", line 220, in do_transaction self.gpgsigcheck(downloadpkgs) File "/usr/lib/python3.4/site-packages/dnf/cli/cli.py", line 251, in gpgsigcheck if not sys.stdin.isatty() and not ay: AttributeError: 'NoneType' object has no attribute 'isatty' I believe the version of dnf is: dnf-1.1.3-1.fc23.noarch
I should say that the reason that stdin is not connected to anything is a bug in libguestfs (see bug 1280029). But I still think this is also a bug in dnf because it should do something like: if (sys.stdin and not sys.stdin.isatty ()) and not ay: [etc]
Looks like James already filed the dnf bug. *** This bug has been marked as a duplicate of bug 1278382 ***