So I was wondering ... Say you have two threads 
my $thread1 = new Thread \&Sub1;
my $thread2 = new Thread \&Sub2;

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and Sub1 has something like: 
select (LOCALFILEHANDLE);
sleep(5);
print "hi";
sleep(5);
select(STDOUT);

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and Sub 2 has something like: 
select (ANOTHERFILEHANDLE);
sleep(4);
print "By";
sleep(2);
select (YETANOTHERFILEHANDLE);

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Which filehandle ends up selected, say, after the dispatched threads return? And furthermore, what happens when you do something funny in a thread (like undef $/) while another thread may be mid-file-read. I guess my question is, is IO thread-safe?

In reply to Threads and FileHandles by robblin

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