Actually, the OP already has IO::Handle loaded (via IO::Socket via IO::Socket::INET), so it's free for him.

For others, it has a one-time cost of 100ms.

>perl -le"use Time::HiRes qw( time ); $stime=time; require IO::Handle;
+ $etime=time; print $etime-$stime;"
0.082003116607666

>perl -le"use Time::HiRes qw( time ); $stime=time; require IO::Handle;
+ $etime=time; print $etime-$stime;"
0.0974130630493164

>perl -le"use Time::HiRes qw( time ); $stime=time; require IO::Handle;
+ $etime=time; print $etime-$stime;"
0.120858192443848
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It's up to them if that's acceptable or not. If it's not, I suggest copying autoflush out of IO::Handle and call it as follows rather than twiddling with select and $| directly.

autoflush(HANDLE, 1);
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