Console

A Console wraps the guest's serial console — the host writes to and reads from QEMU's chardev that the guest has bound to /dev/hvc0.

Constructing

Source	Returns
`vm:console()`	The guest's console. Always succeeds; underlying chardev access is checked at the first `:read` / `:read_log` / `:write` call.

Methods

`console:read()`

Returns a ConsoleStream backed by a UnixStream to the QEMU chardev socket. Use the stream's :next / :read_until / :expect / :drain to consume console output incrementally.

The stream is registered with the VM's resource graph, so an open console:read() blocks vm:snapshot() from succeeding silently — the snapshot precondition reports "live console stream" with creation site.

Errors with console:read: VMM does not expose a console socket if the VMM backend doesn't surface a chardev path (rare; the LocalAgent backend does not).

`console:read_log()`

Returns the entire captured console log to date as a Lua string. Snapshot-style; not a stream. Useful for one-shot inspections:

local log = vm:console():read_log()
t:assert(log:find("Welcome to Peios"))

`console:expect(pattern, timeout?)`

Poll the captured log every 50 ms until pattern (a Lua string) appears or timeout lapses. Default timeout: 30 seconds. Returns the matched substring on hit; raises with the pattern in the message on timeout.

This is the simple form for "wait for the kernel to log X." For long-running streams or when you also want to read past-the-match bytes, use console:read():expect(...) instead.

`console:write(data, opts?)`

Write data (Lua string) to the chardev. Opts:

Key	Type	Effect
`timeout`	number (seconds) or string `"500ms"` / `"5s"`	Bound the blocking write. `0` means no timeout.

The legacy timeout_ms integer key is rejected with a clear error (opts.timeout_ms is not supported (use timeout = "500ms" or timeout = 0.5)).

Use this to feed input to interactive console programs, or to pre-populate a getty login.

`console:close()`

No-op in v1. The chardev itself is owned by the VMM; closing the Console userdata is a Lua-level concept only.

test("login as root via console", function(t)
    provium.timeout = "60s"
    local vm = provium:vm("v", "peios"):boot()
    local console = vm:console()
    local stream  = console:read()
    stream:expect("login:", "30s")
    console:write("root\n")
    stream:expect("Password:", "5s")
    console:write("toor\n")
    stream:expect("# ", "5s")
end)

Constructing #

Methods #

console:read() #

console:read_log() #

console:expect(pattern, timeout?) #

console:write(data, opts?) #

console:close() #

Example: drive a getty login #

See also #