Hey Jeff:
I saw your post on the Marist L/390 list. Thought I'd respond to it
privately.
By "file pointers", I assume what your guy is talking about are symbolic
links.
How carried away can you get with symlinks? As carried away as you like as
long as any specific chain of links doesn't exceed 7 (I think that's the
number for Linux, anyway). By a "chain" of links, what I mean is that there
is a maximum of 7 links that can be traversed before a real file has to be
named. 7 is an incredibly high number, if you think about it. To further
explain myself, if a, b, c, d, e, and f are symlinks, and g is a real file,
then this will work (the arrow represents a symlink, just like it does
under 'ls'):
a->b
b->c
c->d
d->e
e->f
f->g
a will now link all the way to g. So will b, c, d, e, and f. But I'm
reasonably sure that this is the limit.
An individual filesystem directory may contain any number of links ...
there is no limit. I think what your guy is trying to do seems reasonable.
In the future, a wiser approach is to have the 150 makefiles he's talking
about be considered "recursive" makefiles ... in other words, code a
makefile in some other directory that potentially calls all of the 150
"target" makefiles. In that "root" makefile, he could have set up makefile
variables to express the paths to use and could have been passed to the
"child" makefiles automagically, which would have spared him the symlink
tricks he now needs to code.
Good luck. Let me know if I can help you out any further ... I've had to
become more or less of a GNU make expert here.
--Jim--
James S. Tison
Senior Software Engineer
TPF Laboratory / Architecture
IBM Corporation
+1 203 486-2835 (voice/fax)
[EMAIL PROTECTED]
"Davis, Jeff"
<[EMAIL PROTECTED] To: [EMAIL PROTECTED]
alileo.com> cc:
Sent by: Linux on Subject: Linux program question
390 Port
<[EMAIL PROTECTED]
IST.EDU>
01/18/2002 09:48
Please respond to
Linux on 390 Port
I have a user doing some programming on our SuSE Linux for S390 system. He
has the following question.
>
> The question for today is:
>
> "How carried away can I get with Linux file pointers?"
>
> Here is my problem. I have about 150 Makefiles in 150 different
> directories that have two pieces of information that need to be changed.
> Not being accustomed to the Linux or Unix world, I have no clever
> utilities to make mass changes that I'm used to in TSOland and now isn't
a
> really good time to learn them as this is a quick and dirty effort to
> demonstrate that a application can be ported from Unix to Linux.
>
> The first is an include library that I need to change from -L/abc/def/ghi
> to -L/zyx/vvvu/tsr.
> Now I recognize that I could reasonably put a pointer in the /abc/def
> directory that points ghi to /zyx/wvu/tsr and all will be well.
>
> The real question is the -ltcl8.0 include in the 150 makefiles. Can I put
> a pointer in the /zyx/wvu/tsr directory named libtcl8.0 that points to
> /zyx/wvu/tsr/libtcl8.3 and get away with it or will the linker explode?
>
>
>
>
>
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