emory is allocated and associated with a key
from within <I>destr_function</I>, that memory may not be reclaimed
because that key's <I>destr_function</I>, may not run again.</P>
<H2><A HREF="#toc3" NAME="sect3">Return Value</A></H2>
<P><B>pthread_key_create</B>, <B>pthread_key_delete</B>, and
<B>pthread_setspecific</B> return 0 on success and a non-zero error
code on failure. If successful, <B>pthread_key_create</B> stores the
newly allocated key in the location pointed to by its <I>key</I>
argument. 
</P>
