This is always a problem when you try to layer line-oriented semantics atop stream-oriented protocols. Especially, when the buffering is done neither at the system level--where select gets its info--nor at the application level--where the application programmer has some control. Ie. In the intermediate layer, which leaves the application and system with differing ideas about the current state of the communications channel.

The only solution I've found is to set the socket into :raw mode, use sysread to get whatever is available, and do the line buffering semantics within the application itself. Ie. Cut out the middle man.

For the longest time I've been under the assumption that this disconnect was unique to Windows. Seems I was wrong, despite having asked the question here on numerous occasions.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
RIP an inspiration; A true Folk's Guy

In reply to Re: poorly documented behaviour of readline() and IO::Select by BrowserUk
in thread poorly documented behaviour of readline() and IO::Select by vsespb

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