[syslinux] SYSLINUX 2.09, 2.10-pre1 released

[ganapathy murali krishnan]

Gebhardt Thomas wrote:
--- snip ---
 
> but still have two problems

> 1. I can escape the menu system and get the syslinux boot prompt with either 
> "ESC" or  "arrow left" in the main menu. Did I do something wrong?

> 2. Can I easily configure the menu system to do something (boot from the
> local disk) after a specified timeout, i.e., can I configure a noninteractive
> default boot?

You did not do anything wrong. The default setup of the menu is to quit 
the menu when the user hits "Esc" or "arrow left".  However with a 
little bit of C programming, you can solve both your problems...

* Default setup (Overview of how mymenu.c works)
initialise menu...
runmenu...
if user chose something 
   do it 
endif


* What your new mymenu.c should do

print "Press any key within 5 seconds.. to active menu..."
clear keyboard buffer
wait for 5 seconds
if keyboard buffer  is not empty
   run "localboot" / "chain.c32 hd0 0"
else
   initialise menu...
   loop:
       runmenu....
       if valid choice
           execute it
       endif
       goto loop
endif

Clearing and checking the kbd buffer can be done through BIOS interrupts.

To sleep for 5 seconds: here is one solution: Note the current time, and 
run an while loop, and exit that loop only when 5 seconds have passed. 
This is considered really bad programming for any multi-tasking OS. But 
hey, our code is the only one which is running now, so we can afford to 
do it.

- Murali

>On Thursday 29 April 2004 17:20, you wrote:
>
>Hi,
>
>  
>
>>Till such a feature comes along, you can implement the same
>>functionality as follows:
>>
>>* Create a menu, with options corresponding to the different isolinux
>>labels
>>* Set pcelinux.cfg to run the menu directly without any wait.
>>
>>This way you get a slightly user friendly interface and the users dont
>>have access to the pxelinux boot prompt.
>>    
>>
>
>I tried to do that 
>
>(pxelinux.cfg:
>
>DEFAULT mymenu.com
>PROMPT 0
>ONTIMEOUT ...
>ONERROR ...
>...
>)
>
>
>but still have two problems
>
>1. I can escape the menu system and get the syslinux boot prompt with either 
>"ESC" or  "arrow left" in the main menu. Did I do something wrong?
>
>2. Can I easily configure the menu system to do something (boot from the
>local disk) after a specified timeout, i.e., can I configure a noninteractive
>default boot?
>
>My intention is as follows:
>I have a bunch of windows hosts, and want to supply the possibility to
>boot a diskless Linux by PXE.
>constraints:
>1. If the user who boots the machine does nothing at all, it should boot
>windows, just as before.
>2. A linux user should not be able to get root privileges by supplying
>additional kernel boot arguments.
>
>Thanks, Thomas
>
>  
>