icinga2 daemon: reap remaining child processes after reload

[Al2Klimov]

... as we may be PID 1.

[Al2Klimov]

Before

icinga@i2:/$ ps -efH
UID        PID  PPID  C STIME TTY          TIME CMD
icinga      77     0  0 15:28 pts/1    00:00:00 bash
icinga     534    77  0 15:31 pts/1    00:00:00   ps -efH
icinga       1     0  0 15:28 pts/0    00:00:00 /usr/lib/x86_64-linux-gnu/icinga
icinga      71     1  0 15:28 pts/0    00:00:00   [icinga2] <defunct>
icinga     114     1  0 15:29 ?        00:00:00   [sleep] <defunct>
icinga     148     1  0 15:29 pts/0    00:00:00   [icinga2] <defunct>
icinga     153     1  0 15:29 ?        00:00:00   [sleep] <defunct>
icinga     185     1  0 15:29 pts/0    00:00:00   [icinga2] <defunct>
icinga     190     1  0 15:29 ?        00:00:00   [sleep] <defunct>
icinga     221     1  0 15:30 pts/0    00:00:00   [icinga2] <defunct>
icinga     226     1  0 15:30 ?        00:00:00   [sleep] <defunct>
icinga     257     1  0 15:30 pts/0    00:00:00   [icinga2] <defunct>
icinga     262     1  0 15:30 ?        00:00:00   [sleep] <defunct>
icinga     293     1  0 15:30 pts/0    00:00:00   [icinga2] <defunct>
icinga     298     1  0 15:30 ?        00:00:00   [sleep] <defunct>
icinga     329     1  0 15:30 pts/0    00:00:00   [icinga2] <defunct>
icinga     334     1  0 15:30 ?        00:00:00   [sleep] <defunct>
icinga     365     1  0 15:30 pts/0    00:00:00   [icinga2] <defunct>
icinga     370     1  0 15:30 ?        00:00:00   [sleep] <defunct>
icinga     401     1  0 15:30 pts/0    00:00:00   [icinga2] <defunct>
icinga     406     1  0 15:30 ?        00:00:00   [sleep] <defunct>
icinga     437     1  0 15:30 pts/0    00:00:00   [icinga2] <defunct>
icinga     442     1  0 15:30 ?        00:00:00   [sleep] <defunct>
icinga     444     1  0 15:30 pts/0    00:00:00   /usr/lib/x86_64-linux-gnu/icin
icinga     473   444  0 15:30 pts/0    00:00:00     /usr/lib/x86_64-linux-gnu/ic
icinga     532   473  0 15:31 ?        00:00:00       sleep 60
icinga@i2:/$

After

icinga@i2:/$ ps -efH
UID        PID  PPID  C STIME TTY          TIME CMD
icinga     113     0  0 16:03 pts/1    00:00:00 bash
icinga     484   113  0 16:06 pts/1    00:00:00   ps -efH
icinga       1     0  0 16:03 pts/0    00:00:00 /usr/lib/x86_64-linux-gnu/icinga
icinga      76     1  0 16:03 ?        00:00:00   [sleep] <defunct>
icinga     157     1  0 16:03 ?        00:00:00   [sleep] <defunct>
icinga     193     1  0 16:03 ?        00:00:00   [sleep] <defunct>
icinga     229     1  0 16:03 ?        00:00:00   [sleep] <defunct>
icinga     265     1  0 16:03 ?        00:00:00   [sleep] <defunct>
icinga     301     1  0 16:03 ?        00:00:00   [sleep] <defunct>
icinga     337     1  0 16:03 ?        00:00:00   [sleep] <defunct>
icinga     373     1  0 16:04 ?        00:00:00   [sleep] <defunct>
icinga     404     1  0 16:04 pts/0    00:00:00   [icinga2] <defunct>
icinga     409     1  0 16:04 ?        00:00:00   [sleep] <defunct>
icinga     411     1  0 16:04 pts/0    00:00:00   /usr/lib/x86_64-linux-gnu/icin
icinga     440   411  0 16:04 pts/0    00:00:00     /usr/lib/x86_64-linux-gnu/ic
icinga     482   440  0 16:06 ?        00:00:00       sleep 60
icinga@i2:/$ kill -HUP 1
icinga@i2:/$ ps -efH
UID        PID  PPID  C STIME TTY          TIME CMD
icinga     113     0  0 16:03 pts/1    00:00:00 bash
icinga     525   113  0 16:06 pts/1    00:00:00   ps -efH
icinga       1     0  0 16:03 pts/0    00:00:00 /usr/lib/x86_64-linux-gnu/icinga
icinga     440     1  0 16:04 pts/0    00:00:00   [icinga2] <defunct>
icinga     482     1  0 16:06 ?        00:00:00   sleep 60
icinga     490     1  9 16:06 pts/0    00:00:00   /usr/lib/x86_64-linux-gnu/icin
icinga     519   490  0 16:06 pts/0    00:00:00     /usr/lib/x86_64-linux-gnu/ic
icinga     524   519  0 16:06 ?        00:00:00       sleep 60
icinga@i2:/$