process 0 ("swapper")

[anish kumar]

On Sat, 2013-02-16 at 18:48 +0200, Kevin Wilson wrote:
> Hi,
> 
> > we see this code in proc_pid_lookup:
> >
> >         tgid = name_to_int(dentry);
> >         if (tgid == ~0U)
> >                 goto out;
It is the error case when name can't be converted to integer i.e.
name is wrong.
> >
> > In other words, if you ask for pid 0, it bails and doesn't return anything.
> 
> Are you sure that this is what it cjecks?
> 
>  ~0U is not 0 but -1;
right
> 
> for example, try:
> 	printf("%d\n",~0U );
> 	printf("%x\n",~0U );	
> 	printf("%x\n",-1 );
> and you get:
> -1
> ffffffff
> ffffffff
> rgs
> Kevin
> 
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