Ok, you have convinced me, as long as the man page and the LTP get fixed.
/Carsten
"Maciej W. Rozycki" wrote:
> On Tue, 25 Jun 2002, Carsten Langgaard wrote:
>
> > > Linux platforms do it this way, e.g. Alpha and IA-64. A SIGSEGV is a
> > > valid response for an invalid address. Remember you test pipe(3) and not
> > > pipe(2).
> >
> > I'm not sure that you mean by pipe(2) and pipe(3), but according to my man
> > page, pipe should return with EFAULT in this case.
>
> pipe(2) is a syscall, while pipe(3) is a library call (see `man 2 intro'
> and `man 3 intro', respectively). You rarely access syscalls directly --
> the system library usually does this for you. Depending on a system
> certain library functions may be trivial syscall wrappers, invoke a number
> of syscalls (see e.g. the stat() family) or be implemented entirely in the
> userland.
>
> > ERRORS
> > EMFILE Too many file descriptors are in use by the pro
> > cess.
> > ENFILE The system file table is full.
> > EFAULT filedes is not valid.
>
> Yep, this denotes such an error is possible and under what conditions. I
> don't think it actually mandates it, at least it's not expressed
> explicitly. Anyway, it's valid for i386 and possibly nothing else. Look
> at the system version it refers to -- my version is: "Linux 0.99.11 23
> July 1993".
>
> A brief search of the web for "EFAULT pipe" reveals confirms others agree
> with me -- the error is not mandatory (the EFAULT vs SIGSEGV issue was
> discussed a few times at least in various contexts -- go search the web).
>
> I believe a SIGSEGV is saner, too -- this way it's harder for an error
> resulting from passing an invalid pointer to remain unnoticed (consider
> some code that passes a pointer to read-only memory and fails to check a
> result of pipe()).
>
> If still in doubt, you may try to discuss the LTP result at
> <linux-kernel@vger.kernel.org>. I don't think anybody wants to rewrite
> pipe(2) for all the platforms that handle it our way.
>
> Maciej
>
> --
> + Maciej W. Rozycki, Technical University of Gdansk, Poland +
> +--------------------------------------------------------------+
> + e-mail: macro@ds2.pg.gda.pl, PGP key available +
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