That's automatic unless you turned on autoflush. 
use IO::Handle qw( );

$fh->autoflush(1);  # Don't buffer.
print $fh "foo"; 

$fh->autoflush(0);  # Use buffer.
print $fh "foo";    # Only sent when buffer is full or flushed.
$fh->flush();       # Send what's in buffer (if anything) now.

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In reply to Re: How to write to Buffer by ikegami
in thread How to write to Buffer by deewanagan

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