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Re: Cleanup Base: fetch


From: Zera William Holladay <zholla1@xxxxxxx>
Date: Thu, 6 Jan 2005 09:50:37 -0600 (CST)


On Thu, 6 Jan 2005, Mads Martin Joergensen wrote:

> Matthew Dillon wrote:
> > :Isn't it better to use the '\0' to make it clear it's a character?
> > :style(9) says this:
> > :
> > :     Do not use ! for tests unless it is a boolean, e.g. use
> > :
> > :     if (*p == '\0')
> > :
> > :     not
> > :
> > :     if (!*p)
> > :
> > :Of course it ends up being personal preference, but anyway, just curious.
> >
> >     Something like '\n' at least has some readability value, but
> >     '\0' doesn't, really.  Or at least, not much.
> >
> >     I guess it's personal preference, I could go either way but I
> >     would tend to just use 0.
>
> Would 0 not be 32-bit and '\0' 8-bit?

GCC knows the difference.  The above code will produce assembler like:

       cmpb $0,(%eax) //compare byte to the address pointed to by eax
       //some jump condition

If you ever have any doubts, try "%gcc -S the_name_of_your_program.c".
This command will produce a filed called "the_name_of_your_program.s",
which is AT&T syntax assembler.  See the man for gcc and info as.

-Zera Holladay



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