Hi, On 06/18/2012 08:34 PM, Pritam Bankar wrote: > Hi, > I have one structure called foo. Address of object of foo(say objfoo) is > passed to ioctl call > > status = ioctl(fd, arg, &objfoo); as objfoo is a pointer to foo: struct something foo; struct somethint *objfoo = &foo; &objfoo therefore is a pointer to a pointer, not sure if you wanted to pass this to the ioctl. > > But during manipulation I am not getting ioctl error 5 (input/output error). > I am more confused about error in dmesg which is > *foo: no-op * you can't work directly on a object in userspace memory as this might be a security issue. There exits a function to copy from user memory area to kernel memory area (copy_from_user; and afterwards copy back to the user; copy_to_user). Cheers, Matthias > > What does no-op indicate? If it is no-operation, how can we relate this > to foo structure? > > Thanks, > Pritam > > > _______________________________________________ > Kernelnewbies mailing list > Kernelnewbies@xxxxxxxxxxxxxxxxx > http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
