Bill Gatliff wrote: >>> + >>> + p->requester = requester; >>> + if (!strcmp(requester, REQUEST_SYSFS)) >>> + p->pid = current->pid; >>> >>> >> This is new.. What's the reason for saving the pid? >> >> > > I've gotten complaints from those who say, "Ok, so it reported 'sysfs' > back to me, but how can I be sure that it's because *I* own it now, and > not another user process?" Seemed easy enough to add the PID so they > can check. Of course, you could argue that I could report just the PID, > and skip the "sysfs" string altogether. I'd be inclined to agree with you. > > Of course, if you are like me and do the request with cat(1), then the > PID is pretty meaningless. :) > For the record, this request activity is mostly advisory. I can't actually implement something where only the requester is subsequently allowed to manipulate the state of the channel. You really wouldn't want to even if it was possible, because then you'd probably lose the ability to control the output using cat(1) and echo(1). I'm just trying to provide a tool that allows users to Play Nice if they choose to. In fact, it's currently possible to manipulate the state of the channel from userspace without requesting ownership first. Not sure I'm happy with that, but since I can't enforce any sort of access restrictions it seems pointless to even go so far as to require ownership... b.g. -- Bill Gatliff Embedded systems training and consulting http://billgatliff.com bgat@xxxxxxxxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-embedded" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
