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From the last lab. Answer in your head, then open to check.
tmux has-session -t name succeeds if it exists: tmux has-session -t name 2>/dev/null || build-it.tmux capture-pane -p -S - -t name (-S - means from the start of its history).No step-by-step this time. Something is crashing on the server, and two logs in ~/project/logs are being written right now.
~/project/logs/api.log and ~/project/logs/worker.log are growing every second. Somewhere in worker.log a job crashed.
incident whose window logs shows both logs side by side, each followed live with tail -f.~/project/answer.txt.logs window.$ ░░░░
incident: 1 windows (created ...)
$ cat answer.txt
░░░░
tmux new -s incident -n logs
tail -f logs/api.log
Ctrl-b %, then in the new pane:
tail -f logs/worker.log
Ctrl-b [, then ?ERROR and Enter finds ERROR job 8812 crashed. Press q, then Ctrl-b d to detach, and:
echo 8812 > answer.txt
You built a live two-log view, dug a crash out of the scrollback, and left it all running for later. That's a typical first ten minutes of an incident.