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List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guix-devel-bounces+larch=yhetil.org@gnu.org Sender: guix-devel-bounces+larch=yhetil.org@gnu.org X-Migadu-Flow: FLOW_IN X-Migadu-Country: US X-Migadu-Queue-Id: 74DBC272B9 X-Spam-Score: -10.87 X-Migadu-Scanner: mx10.migadu.com X-Migadu-Spam-Score: -10.87 X-TUID: arWGHvJTCOs/ Hello Guix! The =E2=80=98wip-logging=E2=80=99 branch of the Shepherd contains changes t= hat allow clients such =E2=80=98herd status=E2=80=99 to display recently-logged messa= ges, like this: --8<---------------cut here---------------start------------->8--- $ ./herd -s sock status test-logging Status of test-logging: It is running since 22:41:51 (7 seconds ago). Running value is 31389. It is enabled. Provides (test-logging). Requires (). Will be respawned. Recent messages: 2023-12-04 22:41:58 logging logging logging logging logging 2023-12-04 22:41:58 logging logging logging logging logging 2023-12-04 22:41:58 logging logging logging logging logging 2023-12-04 22:41:58 logging logging logging logging logging 2023-12-04 22:41:58 logging logging logging logging logging 2023-12-04 22:41:58 logging logging logging logging logging 2023-12-04 22:41:58 logging logging logging logging logging 2023-12-04 22:41:58 logging logging logging logging logging 2023-12-04 22:41:58 logging logging logging logging logging 2023-12-04 22:41:58 logging logging logging logging logging --8<---------------cut here---------------end--------------->8--- Another *cough* popular service manager provides a facility that looks like this and I find it convenient. Internally, shepherd maintains a ring buffer of the last lines printed by each service. To do that, the first step was to establish a connection between the =E2=80=9Clogger=E2=80=9D and the service it=E2=80=99= s associated with=E2=80=94so far, the logging mechanism was started by =E2=80=98fork+exec-command=E2=80= =99, which doesn=E2=80=99t know what service it=E2=80=99s working for. Loggers are no= w actors that services can query to get those last messages. The changes so far look like this: 627ad75 herd: =E2=80=98status=E2=80=99 displays recently-logged messages. 0b44232 service: Communicate recently-logged messages to clients. 823beae service: Associate loggers with services; keep buffer of logged l= ines. cc8ea8a service: Built-in logger logs the PID of the service. 088997a service: Thread the current service to actions. 3302861 service: Move line-by-line log reading to a separate fiber. Thoughts? I suppose that=E2=80=99s maybe more for the next stable series (1.0!) than = for 0.10.x. Cheers, Ludo=E2=80=99.