As a service to the public i translated the first three posts to english. I hope you all understand the rule, which ensures that the biggest possible share of users can participate in the forums. Like it or not, English is the de facto lingua franca of the internet.


Now to the problem itself:

I don't know Linux all too well, but crontab is not the place to do things based on a event, like a reboot. crontab is for doing things repetitively based on time: if you want to run a script every 5 minutes or every third monday in a month or everyday at 5:00 pm, you use cron. In your case you use a "rc-script". The basic design is like that: your system has several different "runlevels" - modes of operation. One runlevel is a single-user mode without any networking, wich is used to debug the system if things went really, really bad. Another runlevel is multi-user, full network, but no graphical login, which is good if your graphics adapter is broken and you have to log on over the network. Read more about runlevels in your man pages.

To change from one runlevel to another there is a command ("telinit"). When this command is issued the following happens: all the services started in this runlevel are stopped (killed), then the runlevel is switched and all the services in the new runlevel are started. Because at boot time there has to be some runlevel initialized all the start-scripts for this runlevel are executed. This stopping/starting is done via so-called "rc-scripts", which reside in "/etc/rc[n].d", where [n] is the number of the runlevel. all these scripts work the same way: they understand a single parameter, which can be "start", "stop" (or "restart").

Here is a basic layout for such an rc-script:

Code:

case "$1" in
     start)
          # ---- do everything to start service here
          ;;

     stop)
          # ---- do everything to stop service here
          ;;

     *)
          echo "Usage: rc-script {start|stop}"
                exit 1
                ;;
esac

exit 0

You could put your command in there instead of in the crontab and it should work. That is: if your command would be correct, which it isn't.

If you use a relative path like "./somewhere" you depend on a specific context: your session has a working directory, in which a directory named "somewhere" resides. If you would change into this directory the path "./somewhere" would not make sense any more, right? When this script is executed (and this is true for crontab scripts alike) there is no such thing as context, because this is not your session any more, but a different one - hence, use absolute paths always!

Furthermore, you might have set environment variables your application depends on. Be aware that these won't be set in an rc-script either. You have to set them there explicitly to be able to use them there. Issue an "env" and analyze the output to find out if this is true for your app.

I hope this helps.

bakunin