[syslinux] isohybrid has 2 variants

[Ady]

> Hi,
> 
> > All the "isohybrid.exe" I know of are based on the Perl variant.
> 
> I just got one from
>   http://www.filewatcher.com/m/isohybrid.exe.39568-0.html
> 
> Its strings seem not to stem from isohybrid.pl.
> 
> Digging in slitaz source brought a shell script (that would be
> variant #5 then):
>   http://hg.slitaz.org/wok/file/313b384e2a06/syslinux/stuff/tools/isohybrid.sh
> 
> But isohybrid.exe must have a different source.
> 
> How about this as source of variant #4 (isohybrid.exe):
> 
>   http://cook.slitaz.org/cooker.cgi?stuff=syslinux/stuff/iso2exe/iso2exe.c
> 
> Despite its name it has:
>   return "Usage: isohybrid.exe file.iso [--forced]\n";
> and many of the other strings which i see in "isohybrid.exe".
> 
 
My initial focus was on (finding) documentation. I hope we are not 
going too much off-topic talking about the isohybrid.exe variant from 
Slitaz, Anyway...

The receipt of the "syslinux-extra" package in Slitaz includes:
 cp -a $src/isohybrid.sh $fs/usr/bin/isohybrid 
 cp -a $src/iso2exe/iso2exe $fs/usr/bin/iso2exe 

(Note: I am intentionally not posting the protocol for the following 
paths.)

*_At the time I am writing this email_*, the current receipt is:
 hg.slitaz.org/wok/file/313b384e2a06/syslinux-extra/receipt 

An additional relevant receipt is the one for "syslinux-tools":
 hg.slitaz.org/wok/file/313b384e2a06/syslinux-tools/receipt 

which is the package that includes isohybrid.exe.

Indeed the isohybrid.sh script currently is:
 
hg.slitaz.org/wok/file/313b384e2a06/syslinux/stuff/tools/isohybrid.sh 


So, using the current isohybrid.in included in official upstream 
Syslinux, perhaps a similar script and makefile could generate a 
matching isohybrid.exe in each official (pre-)release. If it could be 
based on isohybrid.c, even better.

 
> 
> >  http://www.syslinux.org/archives/2014-June/022259.html 
> > suggests that the 2 prior bug reports:
> >  http://www.syslinux.org/archives/2012-May/017843.html 
> >  http://www.syslinux.org/archives/2012-May/017871.html 
> > might not be the only ones.
> 
> Yeah. It also has problems with large (image) file support.
> Already reported in may and diagnosed by hpa:
> 
> http://www.syslinux.org/archives/2014-May/022041.html:
> > The right thing to do is compile it with #define _FILE_OFFSET_BITS 64
> > and change fseek to fseeko with the appropriate type being off_t.
 
This has been already applied in the Syslinux git (zytor repo).
 
> 
> This brings of course the question how to do this on MS-Windows.
> 
> That's why i asked for a DOS exe that can handle 43 bit file byte
> addressing (32 bit ISO block count + 11 bits usual block size)
 
I don't know about that :(.
 
> 
> 
> Further there is the freshly spotted misnomer "AFP" in the help
> text of isohybrid.c. It should be "APM".
> 
> 
> ----------------------------------------------------------------
> Known Variants up to now:
> 
> - isohybrid.in -> isohybrid.pl       from SYSLINUX, no EFI/GPT support
> 
> - isohybrid.c -> isohybrid           from SYSLINUX
> 
> - libisofs/make_isohybrid_mbr.c      from libburnia, needs isohdp[fp]x*.bin
>   -> libisofs, xorriso                               from SYSLINUX
> 
> - isohybrid.sh                       from SliTaz, no EFI/GPT support
> 
> - iso2exe.c -> isohybrid.exe         from SliTaz, no EFI/GPT support
> 
> ----------------------------------------------------------------
 
Good _starting_ point for documentation.
 
> 
> If somebody wants to assess the quality, i would propose to inspect
> the resulting ISOs by xorriso >= 1.3.7
> 
>   xorriso -indev image.iso \
>           -report_el_torito plain \
>           -report_system_area plain 
> 
> It knows El Torito, MBR, GPT, and APM and complains about some known
> flaws or pitfalls.
 
That's great. Since xorriso is not always an available option for 
some users (e.g. other OS), I hope for The Syslinux Project to still 
get help from developers (regarding isohybrid or other matters).
 
> 
> 
> Have a nice day :)
> 
> Thomas
 
Regards,
Ady.