vk-agent: send a command's stderr on the SSH extended-data channel - #6
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shelleu-wallix wants to merge 2 commits into
Open
shelleu-wallix wants to merge 2 commits into
shelleu-wallix wants to merge 2 commits into
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Give a command run over SSH a stream per output: stdout on the channel's data stream, stderr on extended-data type 1, which RFC 4254 reserves for it. Merged onto one stream as they were, a client reading a framed protocol off stdout desynchronized on the first line the command logged, and plain text output hid the problem. Split the channel rather than consume it into a single stream: the two writers share its flow-control window, and the halves carry no close-on-drop that could close the channel ahead of the exit status.
Set SHELL from the passwd entry, as sshd does; vk-agent's own environment is PID 1's and carries none, so scripts that read it — an editor's remote bootstrap among them — fell back to sh. The login-shell fallback each of the three spawn paths spelled out moves into a helper they now share with the session environment.
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A command run over SSH had its stdout and stderr merged onto the channel's data stream. Text output survives that; a framed binary protocol does not — Zed's remote editing hangs at "Starting proxy..." on the first line its proxy logs to stderr. stderr now goes on extended-data type 1, as sshd does. The second commit exports
SHELL, missing for the same reason: vk-agent's environment is PID 1's.New test drives a russh client against the server and fails if the fix is reverted. Workspace green: 1774 tests, clippy, fmt.