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Re: Preloading capability in linux ??///
On Thu, Nov 23, 2000 at 06:17:17PM -0800, Anmol Khirbat wrote:
> On Fri, 24 Nov 2000, Anand Kumria wrote:
> > On Thu, Nov 23, 2000 at 09:04:32AM -0800, Anmol Khirbat wrote:
> > > On Thu, 23 Nov 2000, Anand Kumria wrote:
> > >
> > > > Do you want to create a bit-for-bit disk copy/image? I'd recommend
> > > > dd(1) then.
> > >
> > > What does dd do that cat can't do ?
> > $ man 1 cat | head
> > cat - concatenate files and print on the standard output
> > $ man 1 dd | head
> > dd - convert and copy a file
> > dd can read and write a file in blocks thus speeding up the transfer
> > whereas cat relies on the underlying C library to do it I/O.
> Show me a program that doesn't use the "underlying C library" to do I/O.
If I show you you won't learn -- read up on read(2) and write(2). That is
how a program can do I/O without other things interferring. The C library
does something similiar.
> > dd can also convert from ascii to ebcdic, and do quite a few
> > other things. the man page is illuminating.
> Whats all this got to do with a "bit-for-bit" disk copy?
Your response to my initial answer was (quoted above) "what does dd
do that cat can't do?". I've just told you some of those things.
Why are you ignoring your own question?
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