I'm appending to a string four bytes a time. Almost everything is 2**19 bytes long or shorter. I'd like to pre-grow my string so perl doesn't have to reallocate it each time I grow the string larger than 2**10 .. 2**18. I can never seem to remember the trick for this so I'm penning it as a SoPW. Help me Obi-wan, you're my only hope.

grow( my( $str ), 2**19 );
while ( ... ) {
    $str .= pack 'J', ...; # append four bytes at a time.
}

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In reply to Pre-grow a string by diotalevi

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