What do you mean by a hex file? Do you mean a binary file? If that is the case then look at open and binmode.
Assuming we are dealing with binary data here, not text, you will have to convert the binary into Perl format using unpack. You will need the exact format of the data (this is sometimes the hardest part).
To jump to another location in the file you will need seek.
you will have to convert the binary into Perl format
Are you talking about fixed-width data manipulation or are you talking about the use of pack and unpack to convert between data types?, While the OP hasn't provided any sample input or output we're left to assume things but I am confused by what you meant when you said "Perl format" ....
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