[syslinux] Question of syslinux chainloading

[Lu Wei]

On 2019-4-12 2:48, Ady Ady via Syslinux wrote:
>> I tried this, it worked! And I tried localboot 0x80 again, it worked
>> this time! I cannot make sure what has changed since last try. Anyway,
>> localboot 0x80|0x81, or 0x00, or 0x any digit,  or localboot only
>> without numbers, will show two line quickly:
>> Booting from local disk...
>> Boot error
>> Then jump to fixed HD's boot.ini menu and boot normally.
>  
>  
> I'm glad it is working for you. OTOH, having the same exact behavior when using 
> different LOCALBOOT options _could_ be an indication of a bug (and if that's 
> the case, it would not be the first sign of a bug in LOCALBOOT).
> 

I think I have found the cause of showing "Boot error" then jumping to
boot fixed HD: It must have to do with "syslinux -r"  (Fall back to the
next device on boot failure) option. I may have not used that option
before, and added it when trying. So LOCALBOOT did fail and only
chainloading with "swap" works.

Another thing about LOCALBOOT: I find in the minimal syslinux
environment (no modules path \syslinux copied), "localboot" command will
show "file not found" error, but ".localboot" (begin with dot) could
run, though failed too. And I find there is localboot.c32 in \syslinux
in full environment. So I infer that syslinux, like DOS, has internal
command and external command, and "localboot" is special that it is both
internal and external. It also explains the dot appeared at the
beginning when I press TAB in syslinux boot menu.

-- 
Regards,
Lu Wei
IM:	xmpp:luweitest at riotcat.org
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