On 2016-07-11 16:05:50 +0200, Yves-Alexis Perez wrote: > On Mon, 2016-07-11 at 06:46 -0700, Vincent Lefevre wrote: > > On 2016-07-11 13:03:55 +0200, Yves-Alexis Perez wrote: > > > So it seems stdin is closed for the second login. Could it break dbus- > > > launch/dbus-daemon somehow? > > > > In general, closing stdin is a bad idea, at least under Linux, > > because if a new file needs to be opened by the process or one of > > its descendants, fd 0 will be reused (while it is not expected to > > correspond to stdin), and this may clash with other functions that > > try to read stdin (= fd 0)... > > Well, lightdm is not explicitely closing /dev/stdin. And adding > checks for (fd == 0) before every close() call might not be the best > practice either.
I think that the best thing to do if one doesn't want to leave the fd on stdin may be to redirect it to /dev/null. I suppose that the "close" was not there to save a file descriptor, so that a redirection could be sufficient. Now, it is also possible that the problem would reappear if fd 0 is redirected (there are unfortunately no explanations of the bug in the correction). -- Vincent Lefèvre <vinc...@vinc17.net> - Web: <https://www.vinc17.net/> 100% accessible validated (X)HTML - Blog: <https://www.vinc17.net/blog/> Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)
