[Proj] libproj4 thread safety

[Gerald Evenden]

Returning to an old subject.

As noted before, pj_strerrno  appears to be the only current problem
restricting libproj4 from working in a threads environment.

This appears solvable by using a variant of the errno.h method.

At the moment, I cannot see anyway to implement an errno method
with the same transparency that the U**X library provides.  It would
appear that the user would have to do some extra extra code/calls to
initialize pj_errno for  threads operation and not simply use the
libproj4 library as is---like one uses the libc library.

It appears to me that setting up special calls related to TSD is 
required
that cannot be hidden in a system that works in both the thread
and linear mode.

Is my assessment correct.?

Comments please.

Thank-you.
_____________________________________
Jerry and the low riders: Daisy Mae and Joshua.
"The whole religious complexion of the modern world is due to the
absence from Jerusalem of a lunatic asylum." Havelock Ellis, 1914