+/*
+ * Debug with GDB:
+ *
+ * (gdb) handle SIGUSR1 pass
+ * Signal Stop Print Pass to program Description
+ * SIGUSR1 Yes Yes Yes User defined signal 1
+ * (gdb) handle SIGUSR2 pass
+ * Signal Stop Print Pass to program Description
+ * SIGUSR2 Yes Yes Yes User defined signal 2
+ * (gdb) handle SIGUSR1 noprint
+ * Signal Stop Print Pass to program Description
+ * SIGUSR1 No No Yes User defined signal 1
+ * (gdb) handle SIGUSR2 noprint
+ */