Thank you for your comments. I will hopefully have version 2 of the diff tonight.
On Thu, Jan 12, 2012 at 4:56 AM, Ed Schouten <[email protected]> wrote: > I suspect that not long after we add dup3(), some random person asks us > to implement F_DUP3FD. Any chance you can implement this without using a > system call, but through fcntl()? The goal is to be atomic with the duplication. On Thu, Jan 12, 2012 at 5:08 AM, Kostik Belousov <[email protected]> wrote: > makesyscalls.sh. This makes me seriosly wonder was the patch compiled at > all. It was compiled and tested in a virtual machine. I did however generate this diff differently than the one I tested (I applied my git diff against svn and used the svn diff here) so I may have missed something when doing that. >> + >> + return (do_dup(td, dupflags, (int)uap->from, (int)uap->to, >> + td->td_retval)); > Why casting arguments to int ? I stole this line from sys_dup2. >> + return (0); > Isn't this line never executed ? Yes, this was leftover of some previous version. >> +} >> + >> +/* >> * Duplicate a file descriptor to a particular value. >> * >> * Note: keep in mind that a potential race condition exists when closing >> @@ -912,6 +945,9 @@ >> fdp->fd_lastfile = new; >> *retval = new; >> >> + if (flags & DUP_CLOEXEC) >> + fdp->fd_ofileflags[new] |= UF_EXCLOSE; >> + > It is better to handle UF_EXCLOSE at the time of assignment to > fdp->fd_ofileflags[new] just above, instead of clearing UF_EXCLOSE > and then setting it. > > That said, I am not sure that we shall copy the O_CLOEXEC crusade from > Linux until it is standartized. And, if copying, I think we shall copy > all bits of the new API, like SOCK_CLOEXEC etc, and not just dup3. If it is standardized I can't see how it will have semantics that differ from the current Linux version and IMHO this is a worthwhile thing to add. > Oh, and it misses the versioning for the new syscall symbols in libc. > The symbols not listed in the Symbol.maps are made local during the > final linkage. Cut me a bit slack, this is my first attempt at adding a syscall ;) -- Eitan Adler _______________________________________________ [email protected] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to "[email protected]"
