osx man page for _lwp_self

_lwp_self(2)                                                       System Calls                                                       _lwp_self(2)

NAME
       _lwp_self - get LWP identifier

SYNOPSIS
       #include <sys/lwp.h>

       lwpid_t _lwp_self(void);

DESCRIPTION
       The _lwp_self() function returns the ID of the calling LWP.

ATTRIBUTES
       See attributes(5)  for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE         |      ATTRIBUTE VALUE        |
       +-----------------------------+-----------------------------+
       |MT-Level                     |Async-Signal-Safe            |
       +-----------------------------+-----------------------------+

SEE ALSO
       attributes(5)

SunOS 5.10                                                          8 Aug 2001                                                        _lwp_self(2)