RE: [PATCH v6 0/2] Enable capsule loader interface for efi firmware updating

[Kweh, Hock Leong]

> -----Original Message-----
> From: Borislav Petkov [mailto:bp@xxxxxxxxx]
> Sent: Saturday, October 03, 2015 5:06 PM
> On Sat, Oct 03, 2015 at 03:18:41AM +0000, Kweh, Hock Leong wrote:
> > > What does the error case look like? A standard glibc message about
> > > write(2) failing?
> > >
> >
> > Any upload fail error like -ENOMEM, -EINVAL, -EIO as well as error
> > returned by efi_capsule_update() API.
> 
> All I'm asking is, how does the user know that the upload didn't succeed?
> 

I think it should depend on user app about which API they are using.
If they are using syscall then errors would be returned through write(2).
If they are using libc APIs fwrite, fputs and fprintf, then the errors would
return through those APIs. However, this design is targeting the simple
upload action "cat capsule.bin > /dev/efi_capsule_loader", so the errors
should be returned through cat() or I/O redirection mechanism from
shell terminal. Am I answered your question?

Btw, I have an out topic question: I do notice you guys wrote in the message
that a function look like write(2) or close(2). What actually the "2" mean there?

Thanks & regards,
Wilson