in reply to Re^2: Perl Alarm Not Working
in thread Perl Alarm Not Working

the LWP stuff will be [interuptable]

You sure?

When I run the following two one liners, 'here' is printed after 30 seconds--when the server times out--not after 10 as it would be if the alarm had interupted the socket read. 

C:\test>start /b perl -MIO::Socket 
-E"$s=IO::Socket::INET->new(Listen=>1,LocalPort=>12345);$c=$s->accept;
+sleep 30"

C:\test>perl -MIO::Socket 
-E"$s=IO::Socket::INET->new('localhost:12345');eval{alarm 10;<$s>};pri
+nt'here'"
here

[download]
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.

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Re^4: Perl Alarm Not Working
by afoken (Chancellor) on Dec 19, 2010 at 22:16 UTC 
    C:\test>start /b perl -MIO::Socket 
-E"$s=IO::Socket::INET->new(Listen=>1,LocalPort=>12345);$c=$s->accept;
+sleep 30"

C:\test>perl -MIO::Socket 
-E"$s=IO::Socket::INET->new('localhost:12345');eval{alarm 10;<$s>};pri
+nt'here'"
here

    [download]

    Windows has no signals. Not even SIGALRM. Perl emulates them, and the emulation is far from perfection. (It's actually pretty good, given that ugly Windows API.)

    Alexander

    --
    Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)
[reply]
[d/l]

      You're telling me non-useful information I already know. alarm does interupt non-io operations on windows: 

      C:\test>perl -E"$c=0;eval{ alarm 10; ++$c while 1; alarm 0;}"
Terminating on signal SIGALRM(14)

      [download]
      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.
[reply]
[d/l]

        You're telling me non-useful information I already know.

        No, apparently you don't. 

        $ perl -MIO::Socket -E'$s=IO::Socket::INET->new(Listen=>1,LocalPort=>1
+2345);$c=$s->accept; sleep 30' &
[1] 3863

$ perl -MIO::Socket -E'$s=IO::Socket::INET->new("localhost:12345");eva
+l{alarm 10;<$s>};print"here"'
Alarm clock

        [download]

        alarm does interupt non-io operations on windows:

        No, just some. The coverage isn't complete.

[reply]
[d/l]

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