Debian initial experience 3

* Run the user at startupProgram
In RedHat and other Linux releases, You can edit/etc/rc. d/rc. Local
Run the program at startup, but Debian does not have this file. What should I do?

1. Log On As root and create a shell script/etc/init. d/local.
2. Write the content to be executed at startup, as shown in figure
#! /Bin/sh
/Home/INT/bin/datapipe... (run the desired command)
3. Grant local execution permission.
Chmod U + x/etc/init. d/local
4. Add local to the startup Item
Update-rc.d local defaults 80 (what does this command update-rc.d mean I don't understand)

Restart reboot.

Reference:
Http://www.desktop-linux.net/debian-rclocal.htm

* What is a defunct process?
When I use PS-a to view the current process, some processes are followed by defunct What does that mean?

Assume that p is the parent process, and s is the child process from its fork. When s ends, the system must send the exit code of S.
The system will delete the PCB of s after it is received to P. P.
When S has exited, but the system has not sent the exit code to P, if we use PS to view the process column
Table, s will be marked as defunct S is the so-called ''zombie ''process.

Reference:
Http://www.fanqiang.com/a1/b5/20020417/080200185.html