-- 

> From: Poul-Henning Kamp <[EMAIL PROTECTED]>
>>void setctty(char *name) {
>>        (void) revoke(name);
>>        if ((fd = open(name, O_RDWR)) == -1) {
> Isn't there a pretty obvious race between the revoke() and the open() ?
> Wouldn't it in fact make much more sense if revoke(2) was defined as
> int revoke(int fd);    /* kick everybody else off */
> and the code above would look like:
>>        if ((fd = open(name, O_RDWR)) == -1) {
>>        }
>>        (void) revoke(fd);

But, revoke() invalidates all descriptors for the named path, so any
subsequent operations on the open file descriptor would fail, which defeats
the purpose of open(). I think what's needed is some form of serialization
around revoke() and open(). I'm not a master of the init code, but it may be
that the code is inherently non-reentrant, so the original code would then
be okay. 

Paul

Paul A. Scott
mailto:[EMAIL PROTECTED]
http://skycoast.us/pscott/


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