pthread_t in 5.3

[Medi Montaseri]

Daniel Eischen wrote:

>On Thu, 27 Jan 2005, Medi Montaseri wrote:
>
>  
>
>>I am confused about the pthread_t type in FreeBSD 5.3,  can you help..
>>
>>Based on /usr/include/pthread.h,
>>typedef struct  pthread                 *pthread_t;
>>and when I look for the declaration of "struct pthread" , all I find is
>>a forward declaration with a comment that says,
>>
>>/*
>> * Forward structure definitions.
>> *
>> * These are mostly opaque to the user.
>> */
>>struct pthread;
>>
>>That is 'struct pthread' is an opaque type....
>>Then in my application, when I try to find my thread_id, I say
>>
>>cout << "my tid is " << pthread_self() << endl;
>>and I get a hex value. Which is syntactically correct, but semantically
>>in-correct.
>>    
>>
>
>Sorry, what pthread_t is, is not for you to know.  It is up to the
>implementation to define it anyway that it wants.  And is also why
>there is a pthread_equal() function.
>
>  
>
>>I'm not interested in the pointer, I'm interested in the numerical
>>thread ID...
>>    
>>
>
>There is no such thing as defined by POSIX.
>
>  
>
>>Now at this point, you'll think all you have to do is to de-reference
>>the pointer.
>>But since 'struct pthrad' is opaque, gdb and myself are clueless to
>>proceed from here.
>>Can someone shed some light on this please...
>>    
>>
>
>I think you are trying to do something that is non-standard/portable.
>
>--
>DE
>
>  
>
But on linux, a thread_t is
typedef unsigned long int pthread_t;
I guess the idea was if a file descriptor is a int and a socket is an 
int and a process id is an int
then a thread also be an int and people can have an array of those IDs.