What is __thread tls?
    Zera William Holladay 
    zholla1 at uic.edu
       
    Mon Mar 14 18:16:39 PST 2005
    
    
  
On Mon, 14 Mar 2005, Matthew Dillon wrote:
[cut]
> :I was under the impression that each pthread has its own errno???  Perhaps
> :I am not understanding the context.  I'm writing my first threaded
> :application so I had best get this straight sooner rather than later.
> :
> :-Zera
>
>     yup, you are right... see if you can figure out how errno is defined
>     for a threaded program in the current environment.  Hint: it isn't a
>     simple global declaration.
#define errno           (* __error()) /* errno.h */
For threaded applications (per the comment):
The function __error() returns a pointer to a field "error" in the pthread
structure (on line 712 of pthread_private.h).
Otherwise and for the main thread:
__error() is a pointer to a global variable.
If I'm right, then that's pretty cool! :)
-Zera
> 					-Matt
> 					Matthew Dillon
> 					<dillon at xxxxxxxxxxxxx>
>
    
    
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