Re^2: Losing Bits with Pack/Unpack

in reply to Re: Losing Bits with Pack/Unpack
in thread Losing Bits with Pack/Unpack

Is "unpack" byte aligned also? If I have not lost any data with the unpack'(H5)%' step, I am wondering how one would go about reversing the process.

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Re^3: Losing Bits with Pack/Unpack by Eily (Monsignor) on Sep 17, 2020 at 12:42 UTC
Yes unpack is also byte aligned. unpack moves exactly like pack does given the same pattern, except it reads instead of writes. You did lose data with `H5`, that's why some chars were changed. One way to see that is to try "hehlo" or "hemlo" instead of hello. You'll see that you get the same result, because four bits in the byte are replaced by 0000 when pack was only given 5 hex digits for 3 bytes.	[reply] [d/l]

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Re^3: Losing Bits with Pack/Unpack
by Eily (Monsignor) on Sep 17, 2020 at 12:42 UTC

Yes unpack is also byte aligned. unpack moves exactly like pack does given the same pattern, except it reads instead of writes. You did lose data with H5, that's why some chars were changed. One way to see that is to try "hehlo" or "hemlo" instead of hello. You'll see that you get the same result, because four bits in the byte are replaced by 0000 when pack was only given 5 hex digits for 3 bytes.

[reply]
[d/l]

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