I have been reading the pack and unpack syntax a while now. I can figure out some simple things like basic strings, integers, etc. but I am having trouble formulating a template for the following: I have a scalar with 512 bytes just read in from a hard drive. the bytes are as follows: 
16 - Binary data (a UUID) - No idea how to put this in template
16 - Binary data (another UUID) - same
16 - string - A16?
1 byte - a number between 0 and 255 - C1
8 bytes - a 64 bit number - Q1
8 bytes - a 64 bit number - Q1
8 bytes - a 64 bit number - Q1
2 bytes - a 16 bit number - S1

[download]
so my template so far looks like this: '??A16CQQQS'
and my overall line would be: @Values = unpack('??A16CQQQS', $Buffer); but my suspicion is that the A16 will give me 16 separate array elements, unfortunately without any idea how to do the first 2 16 byte values (which need to remain binary, completely unchanged)I cannot test it easily. as well I wonder if I can replace 'QQQ' with Q3 and get 3 separate values, one for each 64 bit number.

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In reply to Trouble understanding pack/unpack syntax. by exodist

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