/etc/system/sysinit

The /etc/system/sysinit file is a script that starts up the main system services. In order to edit this file, you must log in as root.

The sysinit script does the following:

1. It starts slogger, if it isn't yet running.
2. The script starts the pipe manager, pipe. This manager lets you pass the output from one command as input to another; for more information, see "Redirecting input and output" in Using the Command Line.
3. Next, sysinit starts mqueue, which manages message queues, using the "traditional" implementation. If you want to use the alternate implementation of message queues that uses asynchronous messaging, you need to start the mq server. For more information, see the Utilities Reference.
   Note: Starting with release 6.3.0, procnto* manages named semaphores, which mqueue used to do (and still does, if it detects that procnto isn't doing so).
4. If this is the first time you've rebooted after installing the OS, sysinit runs /etc/rc.d/rc.setup-once, which creates various directories and swap files.
5. Next, sysinit sets the _CS_TIMEZONE configuration string to the value stored in /etc/TIMEZONE. If this file doesn't exist, sysinit sets the time zone to be UTC, or Coordinated Universal Time (formerly Greenwich Mean Time). For more information, see "Setting the time zone" in Configuring Your Environment.
6. If /etc/rc.d/rc.rtc exists and is executable, sysinit runs it to set up the realtime clock.

   We recommend that you set the hardware clock to UTC time and use the _CS_TIMEZONE configuration string or the TZ environment variable to specify your time zone. The system displays and interprets local times and automatically determines when daylight saving time starts and ends.

   This means that you can have dial-up users in different time zones on the same computer, and they can all see the correct current local time. It also helps when transmitting data from time zone to time zone. You stamp the data with the UTC time stamp, and all of the computers involved should have an easy time comparing time stamps in one time zone to time stamps in another.

   Some operating systems, such as Windows, set the hardware clock to local time. If you install Windows and Neutrino on the same machine, you should set the hardware clock to local time by executing the following command as root and putting it into /etc/rc.d/rc.rtc:

   rtc -l hw
     

7. After setting up the clock, sysinit sets the HOSTNAME environment variable to be the name of the host system. It gets this name from the hostname command, or from /etc/HOSTNAME if that doesn't succeed.
   Note: A hostname can consist only of letters, numbers, and hyphens, and must not start or end with a hyphen. For more information, see RFC 952.
8. Then, sysinit runs /etc/rc.d/rc.devices to enumerate your system's devices (see "Device enumeration," below). This starts io-pkt* as well as various other drivers, depending on the hardware detected.
9. If /etc/system/config/useqnet exists and io-pkt is running, sysinit initializes Neutrino native networking (see the Using Qnet for Transparent Distributed Processing chapter in this guide, and lsm-qnet.so in the Utilities Reference).
10. Next, sysinit runs the system-initialization script, /etc/rc.d/rc.sysinit (see below).
11. If that fails, sysinit tries to become a sh or, if that fails, a fesh, so that you at least have a shell if all else fails.