Re: PAR::Lipo?

On Jun 8, 2006, at 11:15 PM, Chris Dolan wrote:

> [snip]
>
> I propose a "par_lipo" command that works analogously to Apple's  
> "lipo".  par_lipo accepts two PAR executables, one compiled for PPC  
> and one for x86, and merges them into a single larger PAR  
> executable.  The steps involved would be:
>   * compare the embedded .zip containers file-by-file (including  
> libperl)
>     - if the file is present in one PAR and missing in the other, die
>     - if the file is already Universal in either PAR, keep that one
>     - if the file is single-architecture binary, merge via Apple's  
> "lipo" and reinsert
>     - if the file is not binary and is byte-wise different in the  
> two PARs, die
>     - if the file is not binary and is the same in both PARs, keep  
> it as-is
>   * create a "lipo"d header for the executable
>
> [snip]

I have successfully implemented the first bullet above.  However the  
second bullet has proved to be hard because the process by which parl  
creates a standalone executable is extremely complicated.

Is there documentation somewhere of what comprises the non-ZIP  
portion of a PAR standalone executable and/or a PAR standalone  
script?  Most importantly: besides the ZIP portion, does the PAR exe  
ever access its data via file access or just via function calls (like  
the way it extracts libperl and par via the file2c.pl WRITE_load_me_X 
() macros)?

Is there a way to ask PAR to create an empty header with no ZIP  
section?  If so, I think I could do that once for PPC and once for  
x86, then lipo them, then tack on the ZIP section.

Thanks in advance for any advice.  If I can get this solved before  
YAPC::NA, I'll present the technique there.
Chris
--
Chris Dolan, Software Developer, Clotho Advanced Media Inc.
608-294-7900, fax 294-7025, 1435 E Main St, Madison WI 53703
vCard: http://www.chrisdolan.net/ChrisDolan.vcf

Clotho Advanced Media, Inc. - Creators of MediaLandscape Software  
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