Re: Supporting arbitrary file attributes

[Joerg Schilling]

>From: Eli Zaretskii <address@hidden>

>> People who like to add support for DOS file flags to the current extended 
>> flag
>> implementation are welcome.

>I doubt that anyone would invest the significant effort required to port 
>another Tar program to the DOS environment (or native Windows environment, 
>for that matter).  The file flags are the least of your problems: Tar deals 
>with intimate details of the underlying filesystem, and thus is generally 
>very hard to port to non-Posix systems, given the Posix heritage of the 
>mainline code.

How about lokking into star's sources?
Star uses abstract internal data structures. Porting star to Cygwin mainly 
ended up in introducing a line like:

setmode(fileno(tarf), O_BINARY); 

And some code to make star know about the 2 second granularity of the DOS
filesystem.

>I ported GNU Tar 1.12.x to MS-DOS and MS-Windows, and I can tell you that 
>it was a kind of effort I would never wish to go through again.  (You can 
>see the results at http://www.simtel.net/pub/djgpp/v2gnu/.)  That is why 
>I didn't roll back that port into Tar 1.13.x series--the pain of going 
>through all that code is just too much for me...

Sorry I cannot find any description about porting problems on this page.

But you may have had the same unneeded problems like in GNUmake.
If I look into the GNUmake sources, I find a lot of Cygwin specific code.
If you look into smake sources, you will not find a single Cygwin
specific line. And smake runs smoothly on Cygwin, even with filenames
thaat contain backslashes.

>Of course, it could be that star is so much more portable than GNU Tar 
>that all my doubts are irrelevant (I never looked at the star sources)...

Star _is_ much more portable than GNUtar.
It is build on top of the Schily makefile system which help a lot with
portabnility issues and star uses more abstract internal data structures than
GNUtar. Maybe one reason that helps to integrate new things into star is
that I did several rewrites within the last 20 years of star's life.

Jörg

 EMail:address@hidden (home) Jörg Schilling D-13353 Berlin
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