[SOLVED] Startup script.. I know its basic...

[PavedWave]

My first post on these forums so I'd like to say hello all.

Im fairly new to linux, have learnt to do a lot in it but still need to learn some basic things I haven't done before.

Yes, I've tried searching it, have attempted making it work and am getting nowhere..

Here goes,
I'm trying to create a startup script to run "echo low > /sys/class/drm/card0/device/power_profile" (sets the graphics card to a low power mode).

As I understand I should create a file in init.d, chmod +x to make it executable... and it's not working.

Please note this is the only line I entered in the script, am I missing something? Or my other guess is that it is not working because it needs to be run after log in?

Thanks for bearing with me

Also a question, why is there generally a "#! /bin/sh" as the first line in a script, as I understand the # makes it so the line isn't read?

[drnetsys]

#! /bin/bash or csh or sh is so that no matter what shell you are using it knows what shell it was written in . # makes it as a comment in all lines but the first.

[marko]

Originally Posted by PavedWave

My first post on these forums so I'd like to say hello all.

Im fairly new to linux, have learnt to do a lot in it but still need to learn some basic things I haven't done before.

Yes, I've tried searching it, have attempted making it work and am getting nowhere..

Here goes,
I'm trying to create a startup script to run "echo low > /sys/class/drm/card0/device/power_profile" (sets the graphics card to a low power mode).

As I understand I should create a file in init.d, chmod +x to make it executable... and it's not working.

Please note this is the only line I entered in the script, am I missing something? Or my other guess is that it is not working because it needs to be run after log in?

Thanks for bearing with me

Also a question, why is there generally a "#! /bin/sh" as the first line in a script, as I understand the # makes it so the line isn't read?

The first line is an exception to the # as comment rule, when the shell reads the file and see's #! as the first two characters on line 1, it interprets the rest of the line as an executable to run (here it would be /bin/sh )
If you don't do that, the shell won't run that script. There is a way to run a script without the #! and that is to pass the script filename to the shell as an argument:

sh somescript

But this won't work for an init script. Just put the #!/bin/sh on as the first line and your script should work

for more reference see:
http://en.wikipedia.org/wiki/Shebang_(Unix)

[PavedWave]

Thanks for the quick response,

well my script is now

#!/bin/sh
echo low > /sys/class/drm/card0/device/power_profile

But once booted i still need to run it manually in terminal...

Any Ideas

UPDATE:
after creating /etc/rc.d/rc.local and entering the same into it that now works.
Now, just out of curiosity any idea why this is working but not the file i created called /etc/rc.d/init.d/gpudown

Thanks for the help

[scott32746]

Hello,

Once you create your script in /etc/init.d it need to be link to a run level.
do
ls -ld /etc/rc*.d

Once you decide what rc ( run level ) .d you want to use need to link it with a S99 in front of it
Any number should work.

example:
cd /etc/rc?.d
ln -s /etc/init.d/test S99test

I would think you would want to use /etc/rc5.d

[PavedWave]

Okay that makes perfect snes, I thought I had read about something to do with that, but most didn't mention it so i ignored it.

I'm assuming the default local one I created gets the run level 5 by default? Thanks for the help all, enjoying the learning curve!