[32766] in Perl-Users-Digest
Perl-Users Digest, Issue: 4030 Volume: 11
daemon@ATHENA.MIT.EDU (Perl-Users Digest)
Tue Sep 10 00:09:36 2013
Date: Mon, 9 Sep 2013 21:09:02 -0700 (PDT)
From: Perl-Users Digest <Perl-Users-Request@ruby.OCE.ORST.EDU>
To: Perl-Users@ruby.OCE.ORST.EDU (Perl-Users Digest)
Perl-Users Digest Mon, 9 Sep 2013 Volume: 11 Number: 4030
Today's topics:
Re: exec and named pipe questions <derykus@gmail.com>
Re: exec and named pipe questions <rweikusat@mobileactivedefense.com>
Digest Administrivia (Last modified: 6 Apr 01) (Perl-Users-Digest Admin)
----------------------------------------------------------------------
Date: Sun, 08 Sep 2013 19:06:53 -0700
From: Charles DeRykus <derykus@gmail.com>
Subject: Re: exec and named pipe questions
Message-Id: <l0jag2$rk0$1@speranza.aioe.org>
On 9/8/2013 4:07 AM, Rainer Weikusat wrote:
> Charles DeRykus <derykus@gmail.com> writes:
>
> [FIFO]
>
>> Since the open for read blocks until it's created on the other end,
>> you may want to set the handle non-blocking in case the writer's open
>> failed. (You could add a wait/retry with a timeout to recover from
>> a delayed open)
>>
>> use Fcntl;
>> sysopen($_STDOUT, "fifo_stdout", O_RDONLY|O_NONBLOCK) or die ...'
>>
>> This also avoids the ambiguity of opening nonblocking via '+<' but then
>> not knowing if the writer closed the handle.
>
> Using a mode of +< is not 'a non-blocking open' but an open in
> 'read-write mode'. According to the Linux fifo(4) man page,
> ...
Point taken but of course I was just using "non-blocking" in a
descriptive fashion to describe a perl open that wouldn't block immediately.
[ At times I just have to side with Humpty-Dumpty's looseness rather
than Alice's bafflement. ]
--
Charles DeRykus
------------------------------
Date: Mon, 09 Sep 2013 11:19:37 +0100
From: Rainer Weikusat <rweikusat@mobileactivedefense.com>
Subject: Re: exec and named pipe questions
Message-Id: <87k3iqz492.fsf@sapphire.mobileactivedefense.com>
Charles DeRykus <derykus@gmail.com> writes:
> On 9/8/2013 4:07 AM, Rainer Weikusat wrote:
>> Charles DeRykus <derykus@gmail.com> writes:
>>
>> [FIFO]
>>
>>> Since the open for read blocks until it's created on the other end,
>>> you may want to set the handle non-blocking in case the writer's open
>>> failed. (You could add a wait/retry with a timeout to recover from
>>> a delayed open)
>>>
>>> use Fcntl;
>>> sysopen($_STDOUT, "fifo_stdout", O_RDONLY|O_NONBLOCK) or die ...'
>>>
>>> This also avoids the ambiguity of opening nonblocking via '+<' but then
>>> not knowing if the writer closed the handle.
>>
>> Using a mode of +< is not 'a non-blocking open' but an open in
>> 'read-write mode'. According to the Linux fifo(4) man page,
>> ...
>
> Point taken but of course I was just using "non-blocking" in a
> descriptive fashion to describe a perl open that wouldn't block
> immediately.
Using the same term with two different meanings in the same text is at
least very confusing.
> [ At times I just have to side with Humpty-Dumpty's looseness rather
> than Alice's bafflement. ]
?
------------------------------
Date: 6 Apr 2001 21:33:47 GMT (Last modified)
From: Perl-Users-Request@ruby.oce.orst.edu (Perl-Users-Digest Admin)
Subject: Digest Administrivia (Last modified: 6 Apr 01)
Message-Id: <null>
Administrivia:
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End of Perl-Users Digest V11 Issue 4030
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