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Re: select() hanging after terminal killed

On 29.04.2010 13:28, Matthias Andree wrote:
Am 29.04.2010 12:53, schrieb Thomas Wolff:

[on closed terminal]
On Linux, select() indicates an exception and EIO.
On SunOS, select() indicates both an exception and input (weird),
Not weird, you appear to be misunderstanding select().
An IEEE Std 1003.1 compliant select():

  - only states that a subsequent read() will *not block*
    this includes EOF and error, as they make read() return without blocking)

- makes *no statements about success*
Oh, right, so apparently Linux is wrong here (since it does not report read availability...).

On Cygwin, the following is observed:
* EOF is not signalled on read(); rather EIO is indicated right away.
   (Maybe not too bad, an application can handle that as well.)
* select() with timeout hangs.

Especially the latter can hardly be handled by an application.
Pointers for workarounds: alarm(), signal().
So I could setup alarm() to get myself signal()ed while waiting in a long sleep().
But the granularity is in seconds only, so this is not a substitute for most use cases typically handled by calling select().
Thanks for the information anyway.


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