#!/usr/bin/perl Hi ! I have a little question concerning unpack function I have a binary file, from which I read blocks of 71 bytes (in binmode). I want then unpack the data using unpack function but I somehow don't get its functionality...as I understand it It should return an array containing unpacked data according to the given template.. What I do is to read block of data 
open INF, $FileName or die "\nCan't open $FileName for reading: $!\n";
binmode INF;

while ( ($readBytes = read (INF, $buffer, BLOCK_SIZE )) ){
    
    print 'Read bytes:'.$readBytes."\n";
    
    $BlockCounter++;
    
    @data = unpack('C C C C C C C C C C3 C3 C5 C5 C3 C3 C3 C C3 C C12 
+C20', $buffer);
    $tmp = @data;
    print "Size of DataArray = $tmp\n";
    
  }

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What I don't understand is why the size of the array is not equal to the number of templates in template string passed to unpack function but it is still 71 items big as it is the size of the read block(BLOCK_SIZE = 71). I thought unpack works the way as I wrote it, but I was terribly wrong... Can anyone help me with this ? Otherwise I will just have to use substr functions to cut the buffer into such long parts I need ? Thanks!

In reply to why the unpack doesnt split the data to the array ? by gyre007

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