Allow utils.Daemonize() to not close some fds
Allow utils.Daemonize() to not close some fds

This patch implements an optional parameter to utils.Daemonize() which
allows that function to not close some file descriptors.

This will allow the master daemon to open the listening socket before
fork - in order to be able to notify errors and return a meaningful exit
code, and then when we fork we don't close that fd.

Reviewed-by: imsnah


dimara/ganeti,mbakke/ganeti,andir/ganeti,bitemyapp/ganeti,onponomarev/ganeti,yiannist/ganeti,andir/ganeti,mbakke/ganeti,mbakke/ganeti,ganeti/ganeti,yiannist/ganeti,ganeti/ganeti,onponomarev/ganeti,yiannist/ganeti,andir/ganeti,apyrgio/ganeti,dimara/ganeti,leshchevds/ganeti,ganeti-github-testing/ganeti-test-1,leshchevds/ganeti,leshchevds/ganeti,apyrgio/snf-ganeti,ganeti/ganeti,bitemyapp/ganeti,apyrgio/ganeti,grnet/snf-ganeti,ganeti-github-testing/ganeti-test-1,grnet/snf-ganeti,apyrgio/snf-ganeti