Re: Unixware Patch (Was: Re: Beta2 Tag'd and Bundled ...)

Tom Lane writes:
 > Greg Stark <gsstark@mit.edu> writes:
 > > On the other hand, things like, getpwnam, strtok, etc have non-thread-safe
 > > APIs. They can never be made thread-safe. The *_r versions of these functions
 > > are standardized and required. If they don't exist then the platform simply
 > > does not support threads.
 > 
 > This statement is simply false.  A platform can build thread-safe
 > versions of those "unsafe" APIs if it makes the return values point
 > to thread-local storage.  Some BSDs do it that way.  Accordingly, any
 > simplistic "we must have _r to be thread-safe" approach is
 > incorrect.

No, it's not. Using the _r functions on such systems is BETTER because
the API is clean and the function can be implmented in a reentrant and
thread-safe fashion wuithout the need for thread local storage or
mutex locking.

L.