Re: [PATCH] alternative to sys_indirect, part 1

[Michael Kerrisk]

On Thu, Apr 24, 2008 at 4:49 PM, Ulrich Drepper <drepper@xxxxxxxxxx> wrote:
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>  Michael Kerrisk wrote:
>  > * dup2() -- use fcntl(F_DUPFD) instead
>
>  Wrong.  You cannot implement dup2 with fcntl since the latter won't use
>  a file descriptor which is already in use.

True.  One could add a flag to fcntl() to provide that behavior.

>  > So the alternative to sys_indirect(), at least for the purpose of
>  > O_CLOEXEC and similar, would be to create 5 new system calls (or six,
>  > if one finds the signalfd() hack too ugly, which perhaps it is; or 7
>  > if one doesn't like Alan's suggestion for socket()
>
>  Without changing the socket interfaces (plural, socketpair) there would

Yes, I overlooked socket pair()...

>  have to be 7 new syscalls, with changing socket* to an IMO cleaner
>  interface 9.
>
>
>  Or we just add sys_indirect (which is also usable for other syscall
>  extensions, not just the CLOEXEC stuff) and let userlevel (i.e., me)
>  worry about adding new interfaces to libc.  As you can see, for the more
>  recent interfaces like signalfd I have already added an additional
>  parameter so the number of interface changes would be reduced.
>
>  Somebody please make a call and then let's go on with life.  I don't
>  care much either way anymore.  I do hope nobody thinks this is an issue
>  which can be completely ignored (see, e.g., the bug I pointed to the
>  other day).

Since I had to go search, here it is again
http://bugzilla.redhat.com/show_bug.cgi?id=443321
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