On 6/19/19 11:01 AM, Jeffrey Walton wrote: > Hi Everyone, > > I have a systemd service that automatically applies updates. Looking > at the service history, the service reports failure when it installs > updates due to this: > > if dnf -y update &>/dev/null > then > echo "Upgraded system" > else > echo "Failed to upgrade system" > exit 1 > fi > > The problems seems to be 0, 100 and 200 are success. When updates are > installed either 100 or 200 is returned. Confer, > https://dnf.readthedocs.io/en/latest/command_ref.html . > > I looked through Bash Variables, but I did not see a way to signal the > information to Bash. Confer, > https://www.gnu.org/software/bash/manual/html_node/Bash-Variables.html > . > > How do I tell Bash 0, 100 and 200 are success? (Or, how to tell Bash 1 > is the only failure?)
Neither 100 nor 200 are successes, and the page you linked explains exactly why. The former is only relevant to the subcommand "dnf check-update" and indicates that your system is *not* fully upgraded and you should fix that. The latter indicates that you successfully updated the system, but potentially bad things occurred in the process. You can choose to *ignore* selected errors, however, using Greg's suggestion. There is no option to make bash dramatically redefine its entire internal understanding of how basic unix return codes work. -- Eli Schwartz
signature.asc
Description: OpenPGP digital signature
