How to auto start a script which required csh enviroment

[Ervin Liu]

I have a bourne shell script which is required to be executed in csh.Now, I need to run this script every time when system boot up.I want to embed following command in my start script(/sbin/init.d/..)" su - username -c "csh -c scriptname" >/dev/null 2>&1 " .I am not sure if it is good solution.I would appreciate it very much if you can give me some suggestion.

thanks

[Carlos Fernandez Riera]

TO force execution of csh include in the first line of your script:
#!/usr/bin/csh

[Dan Hetzel]

Hi Ervin,

Scripts in /sbin/init.d (or /sbin/rc?.d) will execute independently of their respective shells.
Simply make sure that the first line of your script reads:
#!/usr/bin/csh
if you want a csh to interpret the script.

Best regards,

Dan

[Sandor Horvath_2]

Hi !

What You wrote it is correct if Your script's first line is good. But You can run it only when mounted /usr filesystem where You find csh. Don't forget it !

regards, Saa.

[Dan Hetzel]

Good point, Sandor !!

[Ervin Liu]

Carlos and dan
Thank you for you suggestion.Do you mean in my start script,let's say /sbin/init.d/my_startscript,I put the first line to
#!/usr/bin/csh.?
I think it should be good solution.But I still want to confirm it.so let me explain the complete case.
The user is called "user1",his default login shell is "/usr/bin/sh".He configured some customrized parameter in /home/user1/.cshrc. Every time when he try to run his bourne shell script "user1_script",he do "csh;user_script".I think the reason that he run "csh" command is that he want to execute /home/user1/.cshrc.I read the user_script,I did not see any relation between user_script and .cshrc.I don't know why user must run csh first,then start his user_script.Anyway,I just want my auto_start script match his procedure.
So do you think that I put the #!/usr/bin/csh in the first line of my start script,which can execute .cshrc and match this user's procedure?
thanks again

[Bruce Regittko_1]

Hi,

Yes, the #!/usr/bin/csh line will cause the rest of the script to be executed by the c shell.

Make sure the #! are the absolute first two characters of the file - no indentation or blank lines above. Otherwise, the line will just be a comment and the script will most likely run under the POSIX shell.

--Bruce

[Dan Hetzel · Accepted solution]

Hi Ervin,

That's it! If your script starts with the following line (without any indentation or space before):
#!/usr/bin/csh
and that, at that time, /usr is mounted, C-shell will be used to interpret the script.

Nevertheless, the file /home/user1/.cshrc won't be run because there is no relation with scripts in /sbin/rc?.d or /sbin/init.d and a user directory.

You can explicitely force that file to be read by putting this line in the script (i.e. as second line):
source /home/user1/.cshrc

Make sure that the /home/user1/.cshrc doesn't use any terminal related command (like echo, tset...) as there won't be any terminal attached to the process at run time.

Best regards,

Dan

[Dan Hetzel]

Ervin,

Another point to keep in mind:
Scripts in /sbin/init.d run as 'root', so make sure this is what you want to do.
Otherwise, your script should contain a line like 'su user1 -c ' if it needs to be run with another user ID.

Dan

[Ervin Liu]

HI Dan
I got it.Thank you for your excellent guide.

regards
ervin

[Dan Hetzel]

You're welcome !
Thanks for the points.

Dan