| ------------------------------------------------------------------------------ | 
 | --                                                                          -- | 
 | --                 GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS                 -- | 
 | --                                                                          -- | 
 | --                   S Y S T E M . O S _ I N T E R F A C E                  -- | 
 | --                                                                          -- | 
 | --                                  S p e c                                 -- | 
 | --                                                                          -- | 
 | --             Copyright (C) 1991-1994, Florida State University            -- | 
 | --             Copyright (C) 1995-2006, Free Software Foundation, Inc.      -- | 
 | --                                                                          -- | 
 | -- GNARL is free software; you can  redistribute it  and/or modify it under -- | 
 | -- terms of the  GNU General Public License as published  by the Free Soft- -- | 
 | -- ware  Foundation;  either version 2,  or (at your option) any later ver- -- | 
 | -- sion. GNARL is distributed in the hope that it will be useful, but WITH- -- | 
 | -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY -- | 
 | -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License -- | 
 | -- for  more details.  You should have  received  a copy of the GNU General -- | 
 | -- Public License  distributed with GNARL; see file COPYING.  If not, write -- | 
 | -- to  the  Free Software Foundation,  51  Franklin  Street,  Fifth  Floor, -- | 
 | -- Boston, MA 02110-1301, USA.                                              -- | 
 | --                                                                          -- | 
 | -- As a special exception,  if other files  instantiate  generics from this -- | 
 | -- unit, or you link  this unit with other files  to produce an executable, -- | 
 | -- this  unit  does not  by itself cause  the resulting  executable  to  be -- | 
 | -- covered  by the  GNU  General  Public  License.  This exception does not -- | 
 | -- however invalidate  any other reasons why  the executable file  might be -- | 
 | -- covered by the  GNU Public License.                                      -- | 
 | --                                                                          -- | 
 | -- GNARL was developed by the GNARL team at Florida State University.       -- | 
 | -- Extensive contributions were provided by Ada Core Technologies, Inc.     -- | 
 | --                                                                          -- | 
 | ------------------------------------------------------------------------------ | 
 |  | 
 | --  This is Darwin pthreads version of this package. | 
 |  | 
 | --  This package includes all direct interfaces to OS services | 
 | --  that are needed by children of System. | 
 |  | 
 | --  PLEASE DO NOT add any with-clauses to this package | 
 | --  or remove the pragma Elaborate_Body. | 
 | --  It is designed to be a bottom-level (leaf) package. | 
 |  | 
 | with Interfaces.C; | 
 | package System.OS_Interface is | 
 |    pragma Preelaborate; | 
 |  | 
 |    subtype int            is Interfaces.C.int; | 
 |    subtype short          is Interfaces.C.short; | 
 |    subtype long           is Interfaces.C.long; | 
 |    subtype unsigned       is Interfaces.C.unsigned; | 
 |    subtype unsigned_short is Interfaces.C.unsigned_short; | 
 |    subtype unsigned_long  is Interfaces.C.unsigned_long; | 
 |    subtype unsigned_char  is Interfaces.C.unsigned_char; | 
 |    subtype plain_char     is Interfaces.C.plain_char; | 
 |    subtype size_t         is Interfaces.C.size_t; | 
 |  | 
 |    ----------- | 
 |    -- Errno -- | 
 |    ----------- | 
 |  | 
 |    function errno return int; | 
 |    pragma Import (C, errno, "__get_errno"); | 
 |  | 
 |    EINTR     : constant := 4; | 
 |    ENOMEM    : constant := 12; | 
 |    EINVAL    : constant := 22; | 
 |    EAGAIN    : constant := 35; | 
 |    ETIMEDOUT : constant := 60; | 
 |  | 
 |    ------------- | 
 |    -- Signals -- | 
 |    ------------- | 
 |  | 
 |    Max_Interrupt : constant := 31; | 
 |    type Signal is new int range 0 .. Max_Interrupt; | 
 |    for Signal'Size use int'Size; | 
 |  | 
 |    SIGHUP     : constant := 1; --  hangup | 
 |    SIGINT     : constant := 2; --  interrupt (rubout) | 
 |    SIGQUIT    : constant := 3; --  quit (ASCD FS) | 
 |    SIGILL     : constant := 4; --  illegal instruction (not reset) | 
 |    SIGTRAP    : constant := 5; --  trace trap (not reset) | 
 |    SIGIOT     : constant := 6; --  IOT instruction | 
 |    SIGABRT    : constant := 6; --  used by abort, replace SIGIOT in the  future | 
 |    SIGEMT     : constant := 7; --  EMT instruction | 
 |    SIGFPE     : constant := 8; --  floating point exception | 
 |    SIGKILL    : constant := 9; --  kill (cannot be caught or ignored) | 
 |    SIGBUS     : constant := 10; --  bus error | 
 |    SIGSEGV    : constant := 11; --  segmentation violation | 
 |    SIGSYS     : constant := 12; --  bad argument to system call | 
 |    SIGPIPE    : constant := 13; --  write on a pipe with no one to read it | 
 |    SIGALRM    : constant := 14; --  alarm clock | 
 |    SIGTERM    : constant := 15; --  software termination signal from kill | 
 |    SIGURG     : constant := 16; --  urgent condition on IO channel | 
 |    SIGSTOP    : constant := 17; --  stop (cannot be caught or ignored) | 
 |    SIGTSTP    : constant := 18; --  user stop requested from tty | 
 |    SIGCONT    : constant := 19; --  stopped process has been continued | 
 |    SIGCHLD    : constant := 20; --  child status change | 
 |    SIGTTIN    : constant := 21; --  background tty read attempted | 
 |    SIGTTOU    : constant := 22; --  background tty write attempted | 
 |    SIGIO      : constant := 23; --  I/O possible (Solaris SIGPOLL alias) | 
 |    SIGXCPU    : constant := 24; --  CPU time limit exceeded | 
 |    SIGXFSZ    : constant := 25; --  filesize limit exceeded | 
 |    SIGVTALRM  : constant := 26; --  virtual timer expired | 
 |    SIGPROF    : constant := 27; --  profiling timer expired | 
 |    SIGWINCH   : constant := 28; --  window size change | 
 |    SIGINFO    : constant := 29; --  information request | 
 |    SIGUSR1    : constant := 30; --  user defined signal 1 | 
 |    SIGUSR2    : constant := 31; --  user defined signal 2 | 
 |  | 
 |    SIGADAABORT : constant := SIGTERM; | 
 |    --  Change this if you want to use another signal for task abort. | 
 |    --  SIGTERM might be a good one. | 
 |  | 
 |    type Signal_Set is array (Natural range <>) of Signal; | 
 |  | 
 |    Unmasked    : constant Signal_Set := | 
 |      (SIGTTIN, SIGTTOU, SIGSTOP, SIGTSTP); | 
 |  | 
 |    Reserved    : constant Signal_Set := | 
 |      (SIGKILL, SIGSTOP); | 
 |  | 
 |    type sigset_t is private; | 
 |  | 
 |    function sigaddset (set : access sigset_t; sig : Signal) return int; | 
 |    pragma Import (C, sigaddset, "sigaddset"); | 
 |  | 
 |    function sigdelset (set : access sigset_t; sig : Signal) return int; | 
 |    pragma Import (C, sigdelset, "sigdelset"); | 
 |  | 
 |    function sigfillset (set : access sigset_t) return int; | 
 |    pragma Import (C, sigfillset, "sigfillset"); | 
 |  | 
 |    function sigismember (set : access sigset_t; sig : Signal) return int; | 
 |    pragma Import (C, sigismember, "sigismember"); | 
 |  | 
 |    function sigemptyset (set : access sigset_t) return int; | 
 |    pragma Import (C, sigemptyset, "sigemptyset"); | 
 |  | 
 |    type siginfo_t is private; | 
 |    type ucontext_t is private; | 
 |  | 
 |    type Signal_Handler is access procedure | 
 |      (signo   : Signal; | 
 |       info    : access siginfo_t; | 
 |       context : access ucontext_t); | 
 |  | 
 |    type struct_sigaction is record | 
 |       sa_handler : System.Address; | 
 |       sa_mask    : sigset_t; | 
 |       sa_flags   : int; | 
 |    end record; | 
 |    pragma Convention (C, struct_sigaction); | 
 |    type struct_sigaction_ptr is access all struct_sigaction; | 
 |  | 
 |    SIG_BLOCK   : constant := 1; | 
 |    SIG_UNBLOCK : constant := 2; | 
 |    SIG_SETMASK : constant := 3; | 
 |  | 
 |    SIG_DFL : constant := 0; | 
 |    SIG_IGN : constant := 1; | 
 |  | 
 |    SA_SIGINFO : constant := 16#0040#; | 
 |  | 
 |    function sigaction | 
 |      (sig  : Signal; | 
 |       act  : struct_sigaction_ptr; | 
 |       oact : struct_sigaction_ptr) return int; | 
 |    pragma Import (C, sigaction, "sigaction"); | 
 |  | 
 |    ---------- | 
 |    -- Time -- | 
 |    ---------- | 
 |  | 
 |    Time_Slice_Supported : constant Boolean := True; | 
 |    --  Indicates wether time slicing is supported. | 
 |  | 
 |    type timespec is private; | 
 |  | 
 |    type clockid_t is private; | 
 |  | 
 |    CLOCK_REALTIME : constant clockid_t; | 
 |  | 
 |    function clock_gettime | 
 |      (clock_id : clockid_t; | 
 |       tp       : access timespec) return int; | 
 |  | 
 |    function To_Duration (TS : timespec) return Duration; | 
 |    pragma Inline (To_Duration); | 
 |  | 
 |    function To_Timespec (D : Duration) return timespec; | 
 |    pragma Inline (To_Timespec); | 
 |  | 
 |    type struct_timeval is private; | 
 |  | 
 |    function To_Duration (TV : struct_timeval) return Duration; | 
 |    pragma Inline (To_Duration); | 
 |  | 
 |    function To_Timeval (D : Duration) return struct_timeval; | 
 |    pragma Inline (To_Timeval); | 
 |  | 
 |    ------------------------- | 
 |    -- Priority Scheduling -- | 
 |    ------------------------- | 
 |  | 
 |    SCHED_OTHER : constant := 1; | 
 |    SCHED_RR    : constant := 2; | 
 |    SCHED_FIFO  : constant := 4; | 
 |  | 
 |    ------------- | 
 |    -- Process -- | 
 |    ------------- | 
 |  | 
 |    type pid_t is private; | 
 |  | 
 |    function kill (pid : pid_t; sig : Signal) return int; | 
 |    pragma Import (C, kill, "kill"); | 
 |  | 
 |    function getpid return pid_t; | 
 |    pragma Import (C, getpid, "getpid"); | 
 |  | 
 |    --------- | 
 |    -- LWP -- | 
 |    --------- | 
 |  | 
 |    function lwp_self return System.Address; | 
 |    --  lwp_self does not exist on this thread library, revert to pthread_self | 
 |    --  which is the closest approximation (with getpid). This function is | 
 |    --  needed to share 7staprop.adb across POSIX-like targets. | 
 |    pragma Import (C, lwp_self, "pthread_self"); | 
 |  | 
 |    ------------- | 
 |    -- Threads -- | 
 |    ------------- | 
 |  | 
 |    type Thread_Body is access | 
 |      function (arg : System.Address) return System.Address; | 
 |    type pthread_t           is private; | 
 |    subtype Thread_Id        is pthread_t; | 
 |  | 
 |    type pthread_mutex_t     is limited private; | 
 |    type pthread_cond_t      is limited private; | 
 |    type pthread_attr_t      is limited private; | 
 |    type pthread_mutexattr_t is limited private; | 
 |    type pthread_condattr_t  is limited private; | 
 |    type pthread_key_t       is private; | 
 |  | 
 |    type pthread_mutex_ptr is access all pthread_mutex_t; | 
 |    type pthread_cond_ptr is access all pthread_cond_t; | 
 |  | 
 |    PTHREAD_CREATE_DETACHED : constant := 2; | 
 |  | 
 |    ----------- | 
 |    -- Stack -- | 
 |    ----------- | 
 |  | 
 |    Stack_Base_Available : constant Boolean := False; | 
 |    --  Indicates wether the stack base is available on this target. | 
 |    --  This allows us to share s-osinte.adb between all the FSU run time. | 
 |    --  Note that this value can only be true if pthread_t has a complete | 
 |    --  definition that corresponds exactly to the C header files. | 
 |  | 
 |    function Get_Stack_Base (thread : pthread_t) return System.Address; | 
 |    pragma Inline (Get_Stack_Base); | 
 |    --  returns the stack base of the specified thread. | 
 |    --  Only call this function when Stack_Base_Available is True. | 
 |  | 
 |    function Get_Page_Size return size_t; | 
 |    function Get_Page_Size return System.Address; | 
 |    pragma Import (C, Get_Page_Size, "getpagesize"); | 
 |    --  returns the size of a page, or 0 if this is not relevant on this | 
 |    --  target | 
 |  | 
 |    PROT_NONE  : constant := 0; | 
 |    PROT_READ  : constant := 1; | 
 |    PROT_WRITE : constant := 2; | 
 |    PROT_EXEC  : constant := 4; | 
 |    PROT_ALL   : constant := PROT_READ + PROT_WRITE + PROT_EXEC; | 
 |  | 
 |    PROT_ON    : constant := PROT_NONE; | 
 |    PROT_OFF   : constant := PROT_ALL; | 
 |  | 
 |    function mprotect (addr : System.Address; | 
 |                       len : size_t; | 
 |                       prot : int) return int; | 
 |    pragma Import (C, mprotect); | 
 |  | 
 |    --------------------------------------- | 
 |    -- Nonstandard Thread Initialization -- | 
 |    --------------------------------------- | 
 |  | 
 |    procedure pthread_init; | 
 |  | 
 |    ------------------------- | 
 |    -- POSIX.1c  Section 3 -- | 
 |    ------------------------- | 
 |  | 
 |    function sigwait (set : access sigset_t; sig : access Signal) return int; | 
 |    pragma Import (C, sigwait, "sigwait"); | 
 |  | 
 |    function pthread_kill (thread : pthread_t; sig : Signal) return int; | 
 |    pragma Import (C, pthread_kill, "pthread_kill"); | 
 |  | 
 |    function pthread_sigmask | 
 |      (how  : int; | 
 |       set  : access sigset_t; | 
 |       oset : access sigset_t) return int; | 
 |    pragma Import (C, pthread_sigmask, "pthread_sigmask"); | 
 |  | 
 |    -------------------------- | 
 |    -- POSIX.1c  Section 11 -- | 
 |    -------------------------- | 
 |  | 
 |    function pthread_mutexattr_init | 
 |      (attr : access pthread_mutexattr_t) return int; | 
 |    pragma Import (C, pthread_mutexattr_init, "pthread_mutexattr_init"); | 
 |  | 
 |    function pthread_mutexattr_destroy | 
 |      (attr : access pthread_mutexattr_t) return int; | 
 |    pragma Import (C, pthread_mutexattr_destroy, "pthread_mutexattr_destroy"); | 
 |  | 
 |    function pthread_mutex_init | 
 |      (mutex : access pthread_mutex_t; | 
 |       attr  : access pthread_mutexattr_t) return int; | 
 |    pragma Import (C, pthread_mutex_init, "pthread_mutex_init"); | 
 |  | 
 |    function pthread_mutex_destroy (mutex : access pthread_mutex_t) return int; | 
 |    pragma Import (C, pthread_mutex_destroy, "pthread_mutex_destroy"); | 
 |  | 
 |    function pthread_mutex_lock (mutex : access pthread_mutex_t) return int; | 
 |    pragma Import (C, pthread_mutex_lock, "pthread_mutex_lock"); | 
 |  | 
 |    function pthread_mutex_unlock (mutex : access pthread_mutex_t) return int; | 
 |    pragma Import (C, pthread_mutex_unlock, "pthread_mutex_unlock"); | 
 |  | 
 |    function pthread_condattr_init | 
 |      (attr : access pthread_condattr_t) return int; | 
 |    pragma Import (C, pthread_condattr_init, "pthread_condattr_init"); | 
 |  | 
 |    function pthread_condattr_destroy | 
 |      (attr : access pthread_condattr_t) return int; | 
 |    pragma Import (C, pthread_condattr_destroy, "pthread_condattr_destroy"); | 
 |  | 
 |    function pthread_cond_init | 
 |      (cond : access pthread_cond_t; | 
 |       attr : access pthread_condattr_t) return int; | 
 |    pragma Import (C, pthread_cond_init, "pthread_cond_init"); | 
 |  | 
 |    function pthread_cond_destroy (cond : access pthread_cond_t) return int; | 
 |    pragma Import (C, pthread_cond_destroy, "pthread_cond_destroy"); | 
 |  | 
 |    function pthread_cond_signal (cond : access pthread_cond_t) return int; | 
 |    pragma Import (C, pthread_cond_signal, "pthread_cond_signal"); | 
 |  | 
 |    function pthread_cond_wait | 
 |      (cond  : access pthread_cond_t; | 
 |       mutex : access pthread_mutex_t) return int; | 
 |    pragma Import (C, pthread_cond_wait, "pthread_cond_wait"); | 
 |  | 
 |    function pthread_cond_timedwait | 
 |      (cond    : access pthread_cond_t; | 
 |       mutex   : access pthread_mutex_t; | 
 |       abstime : access timespec) return int; | 
 |    pragma Import (C, pthread_cond_timedwait, "pthread_cond_timedwait"); | 
 |  | 
 |    Relative_Timed_Wait : constant Boolean := False; | 
 |    --  pthread_cond_timedwait requires an absolute delay time | 
 |  | 
 |    -------------------------- | 
 |    -- POSIX.1c  Section 13 -- | 
 |    -------------------------- | 
 |  | 
 |    PTHREAD_PRIO_NONE    : constant := 0; | 
 |    PTHREAD_PRIO_INHERIT : constant := 1; | 
 |    PTHREAD_PRIO_PROTECT : constant := 2; | 
 |  | 
 |    function pthread_mutexattr_setprotocol | 
 |      (attr     : access pthread_mutexattr_t; | 
 |       protocol : int) return int; | 
 |    pragma Import | 
 |      (C, pthread_mutexattr_setprotocol, "pthread_mutexattr_setprotocol"); | 
 |  | 
 |    function pthread_mutexattr_setprioceiling | 
 |      (attr     : access pthread_mutexattr_t; | 
 |       prioceiling : int) return int; | 
 |    pragma Import | 
 |      (C, pthread_mutexattr_setprioceiling, | 
 |       "pthread_mutexattr_setprioceiling"); | 
 |  | 
 |    type padding is array (int range <>) of Interfaces.C.char; | 
 |  | 
 |    type struct_sched_param is record | 
 |       sched_priority : int;  --  scheduling priority | 
 |       opaque         : padding (1 .. 4); | 
 |    end record; | 
 |    pragma Convention (C, struct_sched_param); | 
 |  | 
 |    function pthread_setschedparam | 
 |      (thread : pthread_t; | 
 |       policy : int; | 
 |       param  : access struct_sched_param) return int; | 
 |    pragma Import (C, pthread_setschedparam, "pthread_setschedparam"); | 
 |  | 
 |    function pthread_attr_setscope | 
 |      (attr            : access pthread_attr_t; | 
 |       contentionscope : int) return int; | 
 |    pragma Import (C, pthread_attr_setscope, "pthread_attr_setscope"); | 
 |  | 
 |    function pthread_attr_setinheritsched | 
 |      (attr            : access pthread_attr_t; | 
 |       inheritsched : int) return int; | 
 |    pragma Import | 
 |      (C, pthread_attr_setinheritsched, "pthread_attr_setinheritsched"); | 
 |  | 
 |    function pthread_attr_setschedpolicy | 
 |      (attr   : access pthread_attr_t; | 
 |       policy : int) return int; | 
 |    pragma Import (C, pthread_attr_setschedpolicy, "pthread_attr_setsched"); | 
 |  | 
 |    function sched_yield return int; | 
 |  | 
 |    --------------------------- | 
 |    -- P1003.1c - Section 16 -- | 
 |    --------------------------- | 
 |  | 
 |    function pthread_attr_init (attributes : access pthread_attr_t) return int; | 
 |    pragma Import (C, pthread_attr_init, "pthread_attr_init"); | 
 |  | 
 |    function pthread_attr_destroy | 
 |      (attributes : access pthread_attr_t) return int; | 
 |    pragma Import (C, pthread_attr_destroy, "pthread_attr_destroy"); | 
 |  | 
 |    function pthread_attr_setdetachstate | 
 |      (attr        : access pthread_attr_t; | 
 |       detachstate : int) return int; | 
 |    pragma Import | 
 |      (C, pthread_attr_setdetachstate, "pthread_attr_setdetachstate"); | 
 |  | 
 |    function pthread_attr_setstacksize | 
 |      (attr      : access pthread_attr_t; | 
 |       stacksize : size_t) return int; | 
 |    pragma Import | 
 |      (C, pthread_attr_setstacksize, "pthread_attr_setstacksize"); | 
 |  | 
 |    function pthread_create | 
 |      (thread        : access pthread_t; | 
 |       attributes    : access pthread_attr_t; | 
 |       start_routine : Thread_Body; | 
 |       arg           : System.Address) return int; | 
 |    pragma Import (C, pthread_create, "pthread_create"); | 
 |  | 
 |    procedure pthread_exit (status : System.Address); | 
 |    pragma Import (C, pthread_exit, "pthread_exit"); | 
 |  | 
 |    function pthread_self return pthread_t; | 
 |    pragma Import (C, pthread_self, "pthread_self"); | 
 |  | 
 |    -------------------------- | 
 |    -- POSIX.1c  Section 17 -- | 
 |    -------------------------- | 
 |  | 
 |    function pthread_setspecific | 
 |      (key   : pthread_key_t; | 
 |       value : System.Address) return int; | 
 |    pragma Import (C, pthread_setspecific, "pthread_setspecific"); | 
 |  | 
 |    function pthread_getspecific (key : pthread_key_t) return System.Address; | 
 |    pragma Import (C, pthread_getspecific, "pthread_getspecific"); | 
 |  | 
 |    type destructor_pointer is access procedure (arg : System.Address); | 
 |  | 
 |    function pthread_key_create | 
 |      (key        : access pthread_key_t; | 
 |       destructor : destructor_pointer) return int; | 
 |    pragma Import (C, pthread_key_create, "pthread_key_create"); | 
 |  | 
 | private | 
 |  | 
 |    type sigset_t is new unsigned; | 
 |  | 
 |    type int32_t is new int; | 
 |  | 
 |    type pid_t is new int32_t; | 
 |  | 
 |    type time_t is new long; | 
 |  | 
 |    type timespec is record | 
 |       tv_sec  : time_t; | 
 |       tv_nsec : int32_t; | 
 |    end record; | 
 |    pragma Convention (C, timespec); | 
 |  | 
 |    type clockid_t is new int; | 
 |    CLOCK_REALTIME : constant clockid_t := 0; | 
 |  | 
 |    type struct_timeval is record | 
 |       tv_sec  : int32_t; | 
 |       tv_usec : int32_t; | 
 |    end record; | 
 |    pragma Convention (C, struct_timeval); | 
 |  | 
 |    -- | 
 |    --  Darwin specific signal implementation | 
 |    -- | 
 |    type Pad_Type is array (1 .. 7) of unsigned; | 
 |    type siginfo_t is record | 
 |       si_signo  : int;               --  signal number | 
 |       si_errno  : int;               --  errno association | 
 |       si_code   : int;               --  signal code | 
 |       si_pid    : int;               --  sending process | 
 |       si_uid    : unsigned;          --  sender's ruid | 
 |       si_status : int;               --  exit value | 
 |       si_addr   : System.Address;    --  faulting instruction | 
 |       si_value  : System.Address;    --  signal value | 
 |       si_band   : long;              --  band event for SIGPOLL | 
 |       pad       : Pad_Type;          --  RFU | 
 |    end record; | 
 |    pragma Convention (C, siginfo_t); | 
 |  | 
 |    type stack_t is record | 
 |       ss_sp    : System.Address; | 
 |       ss_size  : int; | 
 |       ss_flags : int; | 
 |    end record; | 
 |    pragma Convention (C, stack_t); | 
 |  | 
 |    type mcontext_t is new System.Address; | 
 |  | 
 |    type ucontext_t is record | 
 |       uc_onstack  : int; | 
 |       uc_sigmask  : sigset_t;         --  Signal Mask Used By This Context | 
 |       uc_stack    : stack_t;          --  Stack Used By This Context | 
 |       uc_link     : System.Address;   --  Pointer To Resuming Context | 
 |       uc_mcsize   : size_t;           --  Size of The Machine Context | 
 |       uc_mcontext : mcontext_t;       --  Machine Specific Context | 
 |    end record; | 
 |    pragma Convention (C, ucontext_t); | 
 |  | 
 |    -- | 
 |    --  Darwin specific pthread implementation | 
 |    -- | 
 |    type pthread_t is new System.Address; | 
 |  | 
 |    type pthread_lock_t is new long; | 
 |  | 
 |    type pthread_attr_t is record | 
 |       sig    : long; | 
 |       opaque : padding (1 .. 36); | 
 |    end record; | 
 |    pragma Convention (C, pthread_attr_t); | 
 |  | 
 |    type pthread_mutexattr_t is record | 
 |       sig    : long; | 
 |       opaque : padding (1 .. 8); | 
 |    end record; | 
 |    pragma Convention (C, pthread_mutexattr_t); | 
 |  | 
 |    type pthread_mutex_t is record | 
 |       sig    : long; | 
 |       opaque : padding (1 .. 40); | 
 |    end record; | 
 |    pragma Convention (C, pthread_mutex_t); | 
 |  | 
 |    type pthread_condattr_t is record | 
 |       sig    : long; | 
 |       opaque : padding (1 .. 4); | 
 |    end record; | 
 |    pragma Convention (C, pthread_condattr_t); | 
 |  | 
 |    type pthread_cond_t is record | 
 |       sig    : long; | 
 |       opaque : padding (1 .. 24); | 
 |    end record; | 
 |    pragma Convention (C, pthread_cond_t); | 
 |  | 
 |    type pthread_once_t is record | 
 |       sig    : long; | 
 |       opaque : padding (1 .. 4); | 
 |    end record; | 
 |    pragma Convention (C, pthread_once_t); | 
 |  | 
 |    type pthread_key_t is new unsigned_long; | 
 |  | 
 | end System.OS_Interface; |