$ vllm-t4 start                                  # one is already running
vllm-t4: already running (pid 14977) -- 'vllm-t4 status', or 'vllm-t4 stop' first   [exit 1]

$ vllm-t4 bogus
usage: vllm-t4 [start|stop|status|query|log|swap] [nowait]                          [exit 2]

$ vllm-t4 swap                                   # already enabled
vllm-t4: swap already on: /opt1/swapfile (16777212 KB)                              [exit 0]

$ VLLM_T4_RIG=/nonexistent vllm-t4 status
vllm-t4: rig not found: /nonexistent (set VLLM_T4_RIG)                              [exit 1]