Re: while trying to learn pack

[rich.japh@xxxxxxxxx (Richard Lee)]

John W. Krahn wrote:
> Richard Lee wrote:
> > I am begining to read bit of low level(assembly) book to just gain 
> > some knoweldge on inner workings of memory.
> >
> > My quesiton is, if machine is 32 bit, even if it's accessing string 
> > 'A', it will have to fetch 32 bit (instead of 8 bit that requires to 
> > make that letter A ) ?
>
> It depends on the CPU.  An Intel compatible CPU has instructions to 
> access 8 bit values from memory but some CPUs can only access 32 bit 
> aligned data.
>
> > I know this is not a mailing list for this but i figure since it's 
> > closely related to pack, i thought someone would clarify for me.
>
> It is not really related to pack() as pack() is a high level function 
> that can hide the details of the CPUs addressing problems.
>
> > I am reading "step by step assembly language"... I am not sure i will 
> > read the whole thing but i just want to get better inner working of 
> > memory as my c book didn't do enough justice.
>
>
> John
Thanks guys,

One more question, How do I look at binary file using perl? ( I am 
assuming unpack will be able to handle it ).
I am trying to see if I can peak into pcap file w/ unpack... what will 
require? ( I am trying to not use modules to learn )
Idea is to learn the pcap structure and use it to unpack somehow? I am 
not asking for anything specific in order to solve the problem.
I guess just reaching out for general idea. if that's possible.

Meanwhile I will keep reading. thanks for help!!