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Old 12-17-2009, 11:36 AM   #1
billysdomain
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stdin redirect


Hi All,

Could someone be so kind as to give me an example of how i would write an inittab entry which would run a program on boot with sdtin and stdout being redirected to an already established serial terminal?

somthing like

myprog:2345:respawn:/usr/bin/myprog > ttyS0 < ttyS0

That would be great, im a windows man missing an autoexec file at the moment :-(
 
Old 12-17-2009, 01:00 PM   #2
thndrchld
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Quote:
Originally Posted by billysdomain View Post
Hi All,

Could someone be so kind as to give me an example of how i would write an inittab entry which would run a program on boot with sdtin and stdout being redirected to an already established serial terminal?

somthing like

myprog:2345:respawn:/usr/bin/myprog > ttyS0 < ttyS0

That would be great, im a windows man missing an autoexec file at the moment :-(
Does it need to run from inittab?

You might do better to create a script to start it in /etc/init.d and creating a symling in /etc/rc#.d where # is the runlevel you want the program to run in. If you want it in multiple runlevels, put it in each that it would apply to, eg: rc2.d, rc3.d, rc4.d, etc. The symlink should follow the naming convention S(number)(scriptname), like S95myprog

The scripts are ran in numerical order, so put it where you want it in the startup sequence.

As for terminal redirection, you can combine stderr and stdout using 2>&1. I'm not very great at terminal redirection to serial, but you can try playing with named pipes. Try 'man mkfifo' and see if that info helps.
 
Old 12-17-2009, 01:21 PM   #3
catkin
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What thndrchld said about using a boot script (unless you especially want the init respawn feature) except the specifics of the boot process vary between distros so the file-symlink-directory structure described may not exist on your system. If not, which distro are you using?
 
Old 12-17-2009, 02:11 PM   #4
thndrchld
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Well, yeah. I'm so used to debian-based distros I forgot other systems do it differently.
Whoopsie.
 
Old 12-17-2009, 02:59 PM   #5
billysdomain
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Quote:
Originally Posted by catkin View Post
What thndrchld said about using a boot script (unless you especially want the init respawn feature) except the specifics of the boot process vary between distros so the file-symlink-directory structure described may not exist on your system. If not, which distro are you using?
very well pointed out - and your correct

Its uClinux - and i dont have any runlevels as such

Im after the syntax to redirect to the serial terminal more then anything
 
Old 12-17-2009, 03:03 PM   #6
catkin
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Quote:
Originally Posted by thndrchld View Post
Well, yeah. I'm so used to debian-based distros I forgot other systems do it differently.
Whoopsie.
Easy for me to spot the whoopsie -- I've done the same whoopsie at least once
 
  


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