Re: z/OS and libc

On 10/06/2015 17:45, Karl Williamson wrote:
> I'm working on continuing to port perl5 to z/OS.  One test that is 
> failing is beyond my knowledge level.  The Dynaloader module has a 
> function dl_findfile() which looks for libraries in the path.  It is 
> expecting to find libc at least, but is finding nothing.
>
> This test does not work on several platforms, even some Unix-like 
> ones, and my guess is it doesn't work on z/OS either.  But I am hoping 
> someone can give me more information.
>
> One of the comments in the perl source says:
>     # On OS/390, libc.a doesn't really hold anything at all,
>
> And that makes me think that looking for it (and perhaps any Unix-y 
> library) is futile.
What exactly is DynaLoader expecting to do with libc.a? CEE.SCEELIB 
contains binder (newer terminology in z/OS Land for link) commands that 
resolve C run-time calls to entry points in a LL which resides in shared 
memory. That behavior might provide some guidance on how to handle this, 
if it needs to be handled.

Yaroslav, would you mind adding a -V to the command line to the c99 
command for a successful build? It should generate a .l file, which 
(hopefully) should contain the binder output as well as compiler output 
(not as important). I would like to see if the binder output provides a 
clue. (The Fine Manual is missing information; -V is documented for the 
c89 command, but says it is handled differently by the xlc (c99 is an 
alias) command, but, in typical IBM fashion, there's no mention of it 
there…)

BTW, in z/OS USS, standard data sets can be accessed using a UNIX-like 
path, //'data.set.name' or //'data.set.name(member)'.

Cheers,
Ray

-- 
M. Ray Mullins
Roseville, CA, USA
http://www.catherdersoftware.com/
http://www.z390.org/

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