I have a file from which I read the first 3 bytes. The first 11 bits are irrelevant. Then I need to take remaining 13 bits. When the file is viewed in hex editor the first 3 bytes are 47 69 01 hex. Based on this the last 13 bits need to be 901 hex which is "01001 00000001" binary but I could not figure out how to do this. 
my @z = unpack ("B11 B13", $buf);

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gives "0000000100011" binary

I performed this operation by binary mathematics, but I can't use this as a solution because it is not flexible. I need a general solution, that will allow flexibility of choosing different offsets and field width easily. (In general I am parsing a bit aligned structure...) Thanks!

In reply to accessing bits in a file by andreyb051

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