Re: Problem in library code using library functions

[Andreas Jaeger]

"Paolo Faraboschi" <address@hidden> writes:

> Here's a symptom of a problem that may be the proverbial "tip of the 
> iceberg"...
> The following seemingly innocuous code hits the assertion (using glibc-2.2 on 
> a linux system):
> 
>       #include <assert.h>
>       strrchr() { assert(0); }
>       main() {}
> 

> The problem is caused by the fact that something in the init
> sequence of libc (set_progname() from assert.c in this specific
> case) calls strrchr(). Now, if I remember correctly what POSIX says,
> programs should be free to redefine the entry point of any function
> (ok, not level-1 OS calls). Libraries should only refer to secondary
> name definitions of whatever they need for themselves. This is
> clearly not true here. After a quick inspection, I have the
> impression that the polluted name space is actually quite large.

Where is this specified by POSIX?  Please give me the reference -
without any normative reference there will not be any change in this
area.  

ISO C 99 defines strrchr and thereby AFAIU forbids such redefinition
in user space.

Andreas
-- 
 Andreas Jaeger
  SuSE Labs address@hidden
   private address@hidden
    http://www.suse.de/~aj