Hey, I'm trying to get upstart to launch a a java program daemonized using jsvc.
Upstart (annoyingly) doesn't have any support for pid files, but instead monitors system calls to detect forks. You can control whether it's expecting 1 or 2 forks using the "expect fork" and "expect daemon" respectively (http://upstart.ubuntu.com/cookbook/#expect) If I don't pass the -user flag to jsvc, I can get upstart to detect the controller process using "expect fork". However, if I _do_ pass the -user flag (because the java program needs to read some root-owned files on startup, then drop to a non-privileged user) it doesn't pick up the correct process because jsvc has extra forks to check the user passed in is valid ( http://svn.apache.org/viewvc/commons/proper/daemon/branches/1.0.x/src/native/unix/native/jsvc-unix.c?view=markup&pathrev=1460687#l427). You actually get two extra forks, because the process restarts with the given procname. Looking through the code, the only reason I can see for it to fork and check the user is as a fail-early strategy and not create the controller process if it's never going to be able to switch the user. I am thinking of submitting a patch to add a "-disableusercheck" flag which would skip the checkuser call. Is there another reason for the checkuser fork that means removing it would lead to issues? If I submitted such a patch is it likely to be considered? Cheers, Andrew
