> > Index: libc/stdlib/posix_pty.c
> > ===================================================================
> > RCS file: /cvs/src/lib/libc/stdlib/posix_pty.c,v
> > retrieving revision 1.1
> > diff -u -p -r1.1 posix_pty.c
> > --- libc/stdlib/posix_pty.c 3 Dec 2012 20:08:33 -0000 1.1
> > +++ libc/stdlib/posix_pty.c 4 May 2015 04:48:11 -0000
> > @@ -35,13 +35,14 @@ posix_openpt(int oflag)
> > int fd, mfd = -1;
> >
> > /* User must specify O_RDWR in oflag. */
> > - if (!(oflag & O_RDWR)) {
> > + if ((oflag & O_ACCMODE) != O_RDWR ||
> > + (oflag & ~(O_ACCMODE | O_NOCTTY)) != 0) {
> > errno = EINVAL;
> > return -1;
> > }
>
> I don't see the need to use O_ACCMODE here at all. Why not just:
>
> if (!(oflag & O_RDWR) || (oflag & ~(O_RDWR | O_NOCTTY)) != 0)
because this is as ugly as the existing code, but harder to understand.
> or even:
>
> if (oflag != O_RDWR && oflag != (O_RDWR | O_NOCTTY))
because whoever will cut'n'paste this code and then allow another access
mode will screw up.
> > Index: libkvm/kvm.c
> > - if (flag & ~O_ACCMODE) {
> > + if ((flag & ~O_ACCMODE) || (flag != O_RDONLY && flag != O_WRONLY &&
> > + flag != O_RDWR)){
>
> The check against O_ACCMODE seems superfluous here since you added
> the explicit flag value checks.
Agreed.
