Howdy all, I have a medium sized application that I'm optimizing for speed (don't worry, it's actually necessary). Having profiled the code, I've found that a major hotspot is in a read loop where results are being read in and unpacked: 
my @row = unpack("FFFFL", $tchandle->get($curdate));

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The call to get is a major time sink (but not one i can get rid of). The call to unpack is another, lesser, but still significant time sink. I've already done all I can to minimize the number of reads. It occurs to me that since the format string never changes, a routine written in C that just unpacks the string into four floats and a long, without going through the internal overhead of the standard unpack call, might speed things up quite a bit. How would I go about writing a routine in C to unpack a string into four Perl floats and a long? It doesn't have to be especially portable (assume Intel hardware), and getting rid of the Perl floats and replacing them with normal floats is not an option.

In reply to How do I unpack Perl floats in C by Anonymous Monk

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