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Re^5: Stumped with select->can_read (buffered)

by zentara (Archbishop)
on Aug 04, 2012 at 08:00 UTC ( #985394=note: print w/replies, xml ) Need Help??

in reply to Re^4: Stumped with select->can_read (buffered)
in thread Stumped with select->can_read

Would it be horrible (performance wise) to read one byte at a time until I reach a newline character, thus forming a real $line?

It's been done before. :-) It certainly is inefficient. What I would do, is sysread as big of chunks as you can, then concat everything into a temp buffer, then split the buffer on newlines into an @array. If the scalar @array is greater than 1, then you have a line. Return the last @array element to your $temp_buffer, and process the rest of the @array elements as lines. It's called a sliding buffer, and you can google for "perl sliding buffer" for examples.

I'm not really a human, but I play one on earth.
Old Perl Programmer Haiku ................... flash japh
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Re^6: Stumped with select->can_read (concat)
by tye (Sage) on Aug 04, 2012 at 16:48 UTC
    sysread as big of chunks as you can, then concat everything into a temp buffer

    sysread can read onto the end of the buffer, avoiding the need to copy the data again:

    sysread( $fh, $buf, 16*1024, length($buf) );

    - tye        

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