Is it allowed to call .output() more than once on seastar::connected_socket?

[kelbon]

Is it valid to create output each time when writing to socket ?

auto out = sock.output();
co_await out.write(...);
co_await out.close();

Seems like correct code to me, but behaves strange in practice

[xemul]

The output_stream closes the underlying sink on its close, so you cannot do the above trick

[kelbon]

I want to write directly to data sync without output_stream, does sync support 2 'write' operations at one time or not (as output_stream)?

[xemul]

I want to write directly to data sync ...

What is "data sync" you want to write to? There's no such thing in seastar AFAIK

[kelbon]

I want to write directly to data sync ...

What is "data sync" you want to write to? There's no such thing in seastar AFAIK

seastar socket output stream uses data sink to write data

[xemul]

Sink, not sync. OK.
No, in general sinks are not fiber-safe either.