gcc/ada/s-osinte-darwin.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                GNU ADA RUN-TIME LIBRARY (GNARL) COMPONENTS               --
   4 --                                                                          --
   5 --                   S Y S T E M . O S _ I N T E R F A C E                  --
   6 --                                                                          --
   7 --                                  S p e c                                 --
   8 --                                                                          --
   9 --             Copyright (C) 1991-1994, Florida State University            --
  10 --             Copyright (C) 1995-2004, Free Software Foundation, Inc.      --
  11 --                                                                          --
  12 -- GNARL is free software; you can  redistribute it  and/or modify it under --
  13 -- terms of the  GNU General Public License as published  by the Free Soft- --
  14 -- ware  Foundation;  either version 2,  or (at your option) any later ver- --
  15 -- sion. GNARL is distributed in the hope that it will be useful, but WITH- --
  16 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  17 -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
  18 -- for  more details.  You should have  received  a copy of the GNU General --
  19 -- Public License  distributed with GNARL; see file COPYING.  If not, write --
  20 -- to  the Free Software Foundation,  59 Temple Place - Suite 330,  Boston, --
  21 -- MA 02111-1307, USA.                                                      --
  22 --                                                                          --
  23 -- As a special exception,  if other files  instantiate  generics from this --
  24 -- unit, or you link  this unit with other files  to produce an executable, --
  25 -- this  unit  does not  by itself cause  the resulting  executable  to  be --
  26 -- covered  by the  GNU  General  Public  License.  This exception does not --
  27 -- however invalidate  any other reasons why  the executable file  might be --
  28 -- covered by the  GNU Public License.                                      --
  29 --                                                                          --
  30 -- GNARL was developed by the GNARL team at Florida State University.       --
  31 -- Extensive contributions were provided by Ada Core Technologies, Inc.     --
  32 --                                                                          --
  33 ------------------------------------------------------------------------------
  34
  35 --  This is Darwin pthreads version of this package.
  36
  37 --  This package includes all direct interfaces to OS services
  38 --  that are needed by children of System.
  39
  40 --  PLEASE DO NOT add any with-clauses to this package
  41 --  or remove the pragma Elaborate_Body.
  42 --  It is designed to be a bottom-level (leaf) package.
  43
  44 with Interfaces.C;
  45 package System.OS_Interface is
  46    pragma Preelaborate;
  47
  48    subtype int            is Interfaces.C.int;
  49    subtype short          is Interfaces.C.short;
  50    subtype long           is Interfaces.C.long;
  51    subtype unsigned       is Interfaces.C.unsigned;
  52    subtype unsigned_short is Interfaces.C.unsigned_short;
  53    subtype unsigned_long  is Interfaces.C.unsigned_long;
  54    subtype unsigned_char  is Interfaces.C.unsigned_char;
  55    subtype plain_char     is Interfaces.C.plain_char;
  56    subtype size_t         is Interfaces.C.size_t;
  57
  58    -----------
  59    -- Errno --
  60    -----------
  61
  62    function errno return int;
  63    pragma Import (C, errno, "__get_errno");
  64
  65    EINTR     : constant := 4;
  66    ENOMEM    : constant := 12;
  67    EINVAL    : constant := 22;
  68    EAGAIN    : constant := 35;
  69    ETIMEDOUT : constant := 60;
  70
  71    -------------
  72    -- Signals --
  73    -------------
  74
  75    Max_Interrupt : constant := 31;
  76    type Signal is new int range 0 .. Max_Interrupt;
  77    for Signal'Size use int'Size;
  78
  79    SIGHUP     : constant := 1; --  hangup
  80    SIGINT     : constant := 2; --  interrupt (rubout)
  81    SIGQUIT    : constant := 3; --  quit (ASCD FS)
  82    SIGILL     : constant := 4; --  illegal instruction (not reset)
  83    SIGTRAP    : constant := 5; --  trace trap (not reset)
  84    SIGIOT     : constant := 6; --  IOT instruction
  85    SIGABRT    : constant := 6; --  used by abort, replace SIGIOT in the  future
  86    SIGEMT     : constant := 7; --  EMT instruction
  87    SIGFPE     : constant := 8; --  floating point exception
  88    SIGKILL    : constant := 9; --  kill (cannot be caught or ignored)
  89    SIGBUS     : constant := 10; --  bus error
  90    SIGSEGV    : constant := 11; --  segmentation violation
  91    SIGSYS     : constant := 12; --  bad argument to system call
  92    SIGPIPE    : constant := 13; --  write on a pipe with no one to read it
  93    SIGALRM    : constant := 14; --  alarm clock
  94    SIGTERM    : constant := 15; --  software termination signal from kill
  95    SIGURG     : constant := 16; --  urgent condition on IO channel
  96    SIGSTOP    : constant := 17; --  stop (cannot be caught or ignored)
  97    SIGTSTP    : constant := 18; --  user stop requested from tty
  98    SIGCONT    : constant := 19; --  stopped process has been continued
  99    SIGCHLD    : constant := 20; --  child status change
 100    SIGTTIN    : constant := 21; --  background tty read attempted
 101    SIGTTOU    : constant := 22; --  background tty write attempted
 102    SIGIO      : constant := 23; --  I/O possible (Solaris SIGPOLL alias)
 103    SIGXCPU    : constant := 24; --  CPU time limit exceeded
 104    SIGXFSZ    : constant := 25; --  filesize limit exceeded
 105    SIGVTALRM  : constant := 26; --  virtual timer expired
 106    SIGPROF    : constant := 27; --  profiling timer expired
 107    SIGWINCH   : constant := 28; --  window size change
 108    SIGINFO    : constant := 29; --  information request
 109    SIGUSR1    : constant := 30; --  user defined signal 1
 110    SIGUSR2    : constant := 31; --  user defined signal 2
 111
 112    SIGADAABORT : constant := SIGABRT;
 113    --  Change this if you want to use another signal for task abort.
 114    --  SIGTERM might be a good one.
 115
 116    type Signal_Set is array (Natural range <>) of Signal;
 117
 118    Unmasked    : constant Signal_Set :=
 119      (SIGTTIN, SIGTTOU, SIGSTOP, SIGTSTP);
 120
 121    Reserved    : constant Signal_Set :=
 122      (SIGKILL, SIGSTOP);
 123
 124    type sigset_t is private;
 125
 126    function sigaddset (set : access sigset_t; sig : Signal) return int;
 127    pragma Import (C, sigaddset, "sigaddset");
 128
 129    function sigdelset (set : access sigset_t; sig : Signal) return int;
 130    pragma Import (C, sigdelset, "sigdelset");
 131
 132    function sigfillset (set : access sigset_t) return int;
 133    pragma Import (C, sigfillset, "sigfillset");
 134
 135    function sigismember (set : access sigset_t; sig : Signal) return int;
 136    pragma Import (C, sigismember, "sigismember");
 137
 138    function sigemptyset (set : access sigset_t) return int;
 139    pragma Import (C, sigemptyset, "sigemptyset");
 140
 141    type siginfo_t is private;
 142    type ucontext_t is private;
 143
 144    type Signal_Handler is access procedure
 145      (signo   : Signal;
 146       info    : access siginfo_t;
 147       context : access ucontext_t);
 148
 149    type struct_sigaction is record
 150       sa_handler : System.Address;
 151       sa_mask    : sigset_t;
 152       sa_flags   : int;
 153    end record;
 154    pragma Convention (C, struct_sigaction);
 155    type struct_sigaction_ptr is access all struct_sigaction;
 156
 157    SIG_BLOCK   : constant := 1;
 158    SIG_UNBLOCK : constant := 2;
 159    SIG_SETMASK : constant := 3;
 160
 161    SIG_DFL : constant := 0;
 162    SIG_IGN : constant := 1;
 163
 164    SA_SIGINFO : constant := 16#0040#;
 165
 166    function sigaction
 167      (sig  : Signal;
 168       act  : struct_sigaction_ptr;
 169       oact : struct_sigaction_ptr) return int;
 170    pragma Import (C, sigaction, "sigaction");
 171
 172    ----------
 173    -- Time --
 174    ----------
 175
 176    Time_Slice_Supported : constant Boolean := True;
 177    --  Indicates wether time slicing is supported.
 178
 179    type timespec is private;
 180
 181    type clockid_t is private;
 182
 183    CLOCK_REALTIME : constant clockid_t;
 184
 185    function clock_gettime
 186      (clock_id : clockid_t;
 187       tp       : access timespec) return int;
 188
 189    function To_Duration (TS : timespec) return Duration;
 190    pragma Inline (To_Duration);
 191
 192    function To_Timespec (D : Duration) return timespec;
 193    pragma Inline (To_Timespec);
 194
 195    type struct_timeval is private;
 196
 197    function To_Duration (TV : struct_timeval) return Duration;
 198    pragma Inline (To_Duration);
 199
 200    function To_Timeval (D : Duration) return struct_timeval;
 201    pragma Inline (To_Timeval);
 202
 203    -------------------------
 204    -- Priority Scheduling --
 205    -------------------------
 206
 207    SCHED_OTHER : constant := 1;
 208    SCHED_RR    : constant := 2;
 209    SCHED_FIFO  : constant := 4;
 210
 211    -------------
 212    -- Process --
 213    -------------
 214
 215    type pid_t is private;
 216
 217    function kill (pid : pid_t; sig : Signal) return int;
 218    pragma Import (C, kill, "kill");
 219
 220    function getpid return pid_t;
 221    pragma Import (C, getpid, "getpid");
 222
 223    ---------
 224    -- LWP --
 225    ---------
 226
 227    function lwp_self return System.Address;
 228    --  lwp_self does not exist on this thread library, revert to pthread_self
 229    --  which is the closest approximation (with getpid). This function is
 230    --  needed to share 7staprop.adb across POSIX-like targets.
 231    pragma Import (C, lwp_self, "pthread_self");
 232
 233    -------------
 234    -- Threads --
 235    -------------
 236
 237    type Thread_Body is access
 238      function (arg : System.Address) return System.Address;
 239    type pthread_t           is private;
 240    subtype Thread_Id        is pthread_t;
 241
 242    type pthread_mutex_t     is limited private;
 243    type pthread_cond_t      is limited private;
 244    type pthread_attr_t      is limited private;
 245    type pthread_mutexattr_t is limited private;
 246    type pthread_condattr_t  is limited private;
 247    type pthread_key_t       is private;
 248
 249    type pthread_mutex_ptr is access all pthread_mutex_t;
 250    type pthread_cond_ptr is access all pthread_cond_t;
 251
 252    PTHREAD_CREATE_DETACHED : constant := 2;
 253
 254    -----------
 255    -- Stack --
 256    -----------
 257
 258    Stack_Base_Available : constant Boolean := False;
 259    --  Indicates wether the stack base is available on this target.
 260    --  This allows us to share s-osinte.adb between all the FSU run time.
 261    --  Note that this value can only be true if pthread_t has a complete
 262    --  definition that corresponds exactly to the C header files.
 263
 264    function Get_Stack_Base (thread : pthread_t) return System.Address;
 265    pragma Inline (Get_Stack_Base);
 266    --  returns the stack base of the specified thread.
 267    --  Only call this function when Stack_Base_Available is True.
 268
 269    function Get_Page_Size return size_t;
 270    function Get_Page_Size return System.Address;
 271    pragma Import (C, Get_Page_Size, "getpagesize");
 272    --  returns the size of a page, or 0 if this is not relevant on this
 273    --  target
 274
 275    PROT_NONE  : constant := 0;
 276    PROT_READ  : constant := 1;
 277    PROT_WRITE : constant := 2;
 278    PROT_EXEC  : constant := 4;
 279    PROT_ALL   : constant := PROT_READ + PROT_WRITE + PROT_EXEC;
 280
 281    PROT_ON    : constant := PROT_NONE;
 282    PROT_OFF   : constant := PROT_ALL;
 283
 284    function mprotect (addr : System.Address;
 285                       len : size_t;
 286                       prot : int) return int;
 287    pragma Import (C, mprotect);
 288
 289    ---------------------------------------
 290    -- Nonstandard Thread Initialization --
 291    ---------------------------------------
 292
 293    procedure pthread_init;
 294
 295    -------------------------
 296    -- POSIX.1c  Section 3 --
 297    -------------------------
 298
 299    function sigwait (set : access sigset_t; sig : access Signal) return int;
 300    pragma Import (C, sigwait, "sigwait");
 301
 302    function pthread_kill (thread : pthread_t; sig : Signal) return int;
 303    pragma Import (C, pthread_kill, "pthread_kill");
 304
 305    type sigset_t_ptr is access all sigset_t;
 306
 307    function pthread_sigmask
 308      (how  : int;
 309       set  : sigset_t_ptr;
 310       oset : sigset_t_ptr) return int;
 311    pragma Import (C, pthread_sigmask, "sigprocmask");
 312
 313    --------------------------
 314    -- POSIX.1c  Section 11 --
 315    --------------------------
 316
 317    function pthread_mutexattr_init
 318      (attr : access pthread_mutexattr_t) return int;
 319    pragma Import (C, pthread_mutexattr_init, "pthread_mutexattr_init");
 320
 321    function pthread_mutexattr_destroy
 322      (attr : access pthread_mutexattr_t) return int;
 323    pragma Import (C, pthread_mutexattr_destroy, "pthread_mutexattr_destroy");
 324
 325    function pthread_mutex_init
 326      (mutex : access pthread_mutex_t;
 327       attr  : access pthread_mutexattr_t) return int;
 328    pragma Import (C, pthread_mutex_init, "pthread_mutex_init");
 329
 330    function pthread_mutex_destroy (mutex : access pthread_mutex_t) return int;
 331    pragma Import (C, pthread_mutex_destroy, "pthread_mutex_destroy");
 332
 333    function pthread_mutex_lock (mutex : access pthread_mutex_t) return int;
 334    pragma Import (C, pthread_mutex_lock, "pthread_mutex_lock");
 335
 336    function pthread_mutex_unlock (mutex : access pthread_mutex_t) return int;
 337    pragma Import (C, pthread_mutex_unlock, "pthread_mutex_unlock");
 338
 339    function pthread_condattr_init
 340      (attr : access pthread_condattr_t) return int;
 341    pragma Import (C, pthread_condattr_init, "pthread_condattr_init");
 342
 343    function pthread_condattr_destroy
 344      (attr : access pthread_condattr_t) return int;
 345    pragma Import (C, pthread_condattr_destroy, "pthread_condattr_destroy");
 346
 347    function pthread_cond_init
 348      (cond : access pthread_cond_t;
 349       attr : access pthread_condattr_t) return int;
 350    pragma Import (C, pthread_cond_init, "pthread_cond_init");
 351
 352    function pthread_cond_destroy (cond : access pthread_cond_t) return int;
 353    pragma Import (C, pthread_cond_destroy, "pthread_cond_destroy");
 354
 355    function pthread_cond_signal (cond : access pthread_cond_t) return int;
 356    pragma Import (C, pthread_cond_signal, "pthread_cond_signal");
 357
 358    function pthread_cond_wait
 359      (cond  : access pthread_cond_t;
 360       mutex : access pthread_mutex_t) return int;
 361    pragma Import (C, pthread_cond_wait, "pthread_cond_wait");
 362
 363    function pthread_cond_timedwait
 364      (cond    : access pthread_cond_t;
 365       mutex   : access pthread_mutex_t;
 366       abstime : access timespec) return int;
 367    pragma Import (C, pthread_cond_timedwait, "pthread_cond_timedwait");
 368
 369    Relative_Timed_Wait : constant Boolean := False;
 370    --  pthread_cond_timedwait requires an absolute delay time
 371
 372    --------------------------
 373    -- POSIX.1c  Section 13 --
 374    --------------------------
 375
 376    PTHREAD_PRIO_NONE    : constant := 0;
 377    PTHREAD_PRIO_INHERIT : constant := 1;
 378    PTHREAD_PRIO_PROTECT : constant := 2;
 379
 380    function pthread_mutexattr_setprotocol
 381      (attr     : access pthread_mutexattr_t;
 382       protocol : int) return int;
 383    pragma Import
 384      (C, pthread_mutexattr_setprotocol, "pthread_mutexattr_setprotocol");
 385
 386    function pthread_mutexattr_setprioceiling
 387      (attr     : access pthread_mutexattr_t;
 388       prioceiling : int) return int;
 389    pragma Import
 390      (C, pthread_mutexattr_setprioceiling,
 391       "pthread_mutexattr_setprioceiling");
 392
 393    type struct_sched_param is record
 394       sched_priority : int;  --  scheduling priority
 395    end record;
 396
 397    function pthread_setschedparam
 398      (thread : pthread_t;
 399       policy : int;
 400       param  : access struct_sched_param) return int;
 401    pragma Import (C, pthread_setschedparam, "pthread_setschedparam");
 402
 403    function pthread_attr_setscope
 404      (attr            : access pthread_attr_t;
 405       contentionscope : int) return int;
 406    pragma Import (C, pthread_attr_setscope, "pthread_attr_setscope");
 407
 408    function pthread_attr_setinheritsched
 409      (attr            : access pthread_attr_t;
 410       inheritsched : int) return int;
 411    pragma Import
 412      (C, pthread_attr_setinheritsched, "pthread_attr_setinheritsched");
 413
 414    function pthread_attr_setschedpolicy
 415      (attr   : access pthread_attr_t;
 416       policy : int) return int;
 417    pragma Import (C, pthread_attr_setschedpolicy, "pthread_attr_setsched");
 418
 419    function sched_yield return int;
 420
 421    ---------------------------
 422    -- P1003.1c - Section 16 --
 423    ---------------------------
 424
 425    function pthread_attr_init (attributes : access pthread_attr_t) return int;
 426    pragma Import (C, pthread_attr_init, "pthread_attr_init");
 427
 428    function pthread_attr_destroy
 429      (attributes : access pthread_attr_t) return int;
 430    pragma Import (C, pthread_attr_destroy, "pthread_attr_destroy");
 431
 432    function pthread_attr_setdetachstate
 433      (attr        : access pthread_attr_t;
 434       detachstate : int) return int;
 435    pragma Import
 436      (C, pthread_attr_setdetachstate, "pthread_attr_setdetachstate");
 437
 438    function pthread_attr_setstacksize
 439      (attr      : access pthread_attr_t;
 440       stacksize : size_t) return int;
 441    pragma Import
 442      (C, pthread_attr_setstacksize, "pthread_attr_setstacksize");
 443
 444    function pthread_create
 445      (thread        : access pthread_t;
 446       attributes    : access pthread_attr_t;
 447       start_routine : Thread_Body;
 448       arg           : System.Address) return int;
 449    pragma Import (C, pthread_create, "pthread_create");
 450
 451    procedure pthread_exit (status : System.Address);
 452    pragma Import (C, pthread_exit, "pthread_exit");
 453
 454    function pthread_self return pthread_t;
 455    pragma Import (C, pthread_self, "pthread_self");
 456
 457    --------------------------
 458    -- POSIX.1c  Section 17 --
 459    --------------------------
 460
 461    function pthread_setspecific
 462      (key   : pthread_key_t;
 463       value : System.Address) return int;
 464    pragma Import (C, pthread_setspecific, "pthread_setspecific");
 465
 466    function pthread_getspecific (key : pthread_key_t) return System.Address;
 467    pragma Import (C, pthread_getspecific, "pthread_getspecific");
 468
 469    type destructor_pointer is access procedure (arg : System.Address);
 470
 471    function pthread_key_create
 472      (key        : access pthread_key_t;
 473       destructor : destructor_pointer) return int;
 474    pragma Import (C, pthread_key_create, "pthread_key_create");
 475
 476 private
 477
 478    type array_type_1 is array (Integer range 0 .. 3) of unsigned_long;
 479    type sigset_t is record
 480       X_X_sigbits  : array_type_1;
 481    end record;
 482    pragma Convention (C, sigset_t);
 483
 484    type pid_t is new long;
 485
 486    type time_t is new long;
 487
 488    type timespec is record
 489       tv_sec  : time_t;
 490       tv_nsec : long;
 491    end record;
 492    pragma Convention (C, timespec);
 493
 494    type clockid_t is new int;
 495    CLOCK_REALTIME : constant clockid_t := 0;
 496
 497    type struct_timeval is record
 498       tv_sec  : long;
 499       tv_usec : long;
 500    end record;
 501    pragma Convention (C, struct_timeval);
 502
 503    --
 504    --  Darwin specific signal implementation
 505    --
 506    type Pad_Type is array (0 .. 7) of int;
 507    type siginfo_t is record
 508       si_signo  : int;               --  signal number
 509       si_errno  : int;               --  errno association
 510       si_code   : int;               --  signal code
 511       si_pid    : int;               --  sending process
 512       si_uid    : unsigned;          --  sender's ruid
 513       si_status : int;               --  exit value
 514       si_addr   : System.Address;    --  faulting instruction
 515       si_value  : System.Address;    --  signal value
 516       si_band   : long;              --  band event for SIGPOLL
 517       pad       : Pad_Type;          --  RFU
 518    end record;
 519    pragma Convention (C, siginfo_t);
 520
 521    type stack_t is record
 522       ss_sp    : System.Address;
 523       ss_size  : int;
 524       ss_flags : int;
 525    end record;
 526    pragma Convention (C, stack_t);
 527
 528    type mcontext_t is new System.Address;
 529
 530    type ucontext_t is record
 531       uc_onstack  : int;
 532       uc_sigmask  : sigset_t;         --  Signal Mask Used By This Context
 533       uc_stack    : stack_t;          --  Stack Used By This Context
 534       uc_link     : System.Address;   --  Pointer To Resuming Context
 535       uc_mcsize   : size_t;           --  Size of The Machine Context
 536       uc_mcontext : mcontext_t;       --  Machine Specific Context
 537    end record;
 538    pragma Convention (C, ucontext_t);
 539
 540    --
 541    --  Darwin specific pthread implementation
 542    --
 543    type pthread_t is new System.Address;
 544
 545    type pthread_lock_t is new long;
 546
 547    type sched_param_pad is array (0 .. 3) of plain_char;
 548    type sched_param is record
 549       sched_priority : int;
 550       opaque         : sched_param_pad;
 551    end record;
 552    pragma Convention (C, sched_param);
 553    type boolean_t is new int;
 554
 555    type pthread_attr_t is record
 556       sig             : long;
 557       lock            : pthread_lock_t;
 558       detached        : int;
 559       inherit         : int;
 560       policy          : int;
 561       param           : sched_param;
 562       stackaddr       : System.Address;
 563       stacksize       : long;
 564       freeStackOnExit : boolean_t;
 565    end record;
 566    pragma Convention (C, pthread_attr_t);
 567
 568    type pthread_mutexattr_t is record
 569       sig         : long;
 570       prioceiling : int;
 571       protocol    : int;
 572    end record;
 573    pragma Convention (C, pthread_mutexattr_t);
 574
 575    type mach_port_t is new unsigned_long;
 576
 577    type pthread_mutex_t is record
 578       sig         : long;
 579       lock        : pthread_lock_t;
 580       prioceiling : int;
 581       priority    : int;
 582       protocol    : int;
 583       owner       : pthread_t;
 584       next        : pthread_mutex_ptr;
 585       prev        : pthread_mutex_ptr;
 586       busy        : pthread_cond_ptr;
 587       field       : int;
 588       sem         : mach_port_t;
 589    end record;
 590    pragma Convention (C, pthread_mutex_t);
 591
 592    type pthread_condattr_t is record
 593       sig         : long;
 594       unsupported : int;
 595    end record;
 596    pragma Convention (C, pthread_condattr_t);
 597
 598    type pthread_cond_t is record
 599       sig         : long;
 600       lock        : pthread_lock_t;
 601       sem         : mach_port_t;
 602       next        : pthread_cond_ptr;
 603       prev        : pthread_cond_ptr;
 604       busy        : pthread_mutex_ptr;
 605       waiters     : short;
 606       sigspending : short;
 607    end record;
 608    pragma Convention (C, pthread_cond_t);
 609
 610    type pthread_once_t is record
 611       sig  : long;
 612       lock : pthread_lock_t;
 613    end record;
 614    pragma Convention (C, pthread_once_t);
 615
 616    type rwlockattr_rfu_array is array (0 .. 1) of int;
 617
 618    type pthread_rwlockattr_t is record
 619       sig     : long;
 620       pshared : int;
 621       rfu     : rwlockattr_rfu_array;
 622    end record;
 623    pragma Convention (C, pthread_rwlockattr_t);
 624
 625    type rwlock_rfu_array is array (0 .. 2) of int;
 626
 627    type pthread_rwlock_t is record
 628       sig           : long;
 629       lock          : pthread_mutex_t;
 630       state         : int;
 631       read_signal   : pthread_cond_t;
 632       write_signal  : pthread_cond_t;
 633       block_writers : int;
 634       pshared       : int;
 635       rfu           : rwlock_rfu_array;
 636    end record;
 637    pragma Convention (C, pthread_rwlock_t);
 638
 639    type pthread_key_t is new unsigned_long;
 640
 641 end System.OS_Interface;