1 ------------------------------------------------------------------------------
3 -- GNU ADA RUN-TIME LIBRARY (GNARL) COMPONENTS --
5 -- S Y S T E M . O S _ I N T E R F A C E --
9 -- Copyright (C) 1997-2011 Free Software Foundation, Inc. --
11 -- GNARL is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. --
18 -- As a special exception under Section 7 of GPL version 3, you are granted --
19 -- additional permissions described in the GCC Runtime Library Exception, --
20 -- version 3.1, as published by the Free Software Foundation. --
22 -- You should have received a copy of the GNU General Public License and --
23 -- a copy of the GCC Runtime Library Exception along with this program; --
24 -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
25 -- <http://www.gnu.org/licenses/>. --
27 -- GNARL was developed by the GNARL team at Florida State University. --
28 -- Extensive contributions were provided by Ada Core Technologies Inc. --
30 -- The GNARL files that were developed for RTEMS are maintained by On-Line --
31 -- Applications Research Corporation (http://www.oarcorp.com) in coopera- --
32 -- tion with Ada Core Technologies Inc. and Florida State University. --
34 ------------------------------------------------------------------------------
36 -- This is the RTEMS version of this package.
38 -- RTEMS target names are of the form CPU-rtems.
39 -- This implementation is designed to work on ALL RTEMS targets.
40 -- The RTEMS implementation is primarily based upon the POSIX threads
41 -- API but there are also bindings to GNAT/RTEMS support routines
42 -- to insulate this code from C API specific details and, in some
43 -- cases, obtain target architecture and BSP specific information
44 -- that is unavailable at the time this package is built.
46 -- This package encapsulates all direct interfaces to OS services
47 -- that are needed by children of System.
49 -- PLEASE DO NOT add any with-clauses to this package
50 -- or remove the pragma Preelaborate.
51 -- It is designed to be a bottom-level (leaf) package.
54 package System
.OS_Interface
is
57 -- This interface assumes that "unsigned" is a 32-bit entity. This
58 -- will correspond to RTEMS object ids.
60 subtype rtems_id
is Interfaces
.C
.unsigned
;
62 subtype int
is Interfaces
.C
.int
;
63 subtype short
is Interfaces
.C
.short
;
64 subtype long
is Interfaces
.C
.long
;
65 subtype unsigned
is Interfaces
.C
.unsigned
;
66 subtype unsigned_short
is Interfaces
.C
.unsigned_short
;
67 subtype unsigned_long
is Interfaces
.C
.unsigned_long
;
68 subtype unsigned_char
is Interfaces
.C
.unsigned_char
;
69 subtype plain_char
is Interfaces
.C
.plain_char
;
70 subtype size_t
is Interfaces
.C
.size_t
;
76 function errno
return int
;
77 pragma Import
(C
, errno
, "__get_errno");
79 EAGAIN
: constant := 11;
80 EINTR
: constant := 4;
81 EINVAL
: constant := 22;
82 ENOMEM
: constant := 12;
83 ETIMEDOUT
: constant := 116;
89 Num_HW_Interrupts
: constant := 256;
91 Max_HW_Interrupt
: constant := Num_HW_Interrupts
- 1;
92 type HW_Interrupt
is new int
range 0 .. Max_HW_Interrupt
;
94 Max_Interrupt
: constant := Max_HW_Interrupt
;
96 type Signal
is new int
range 0 .. Max_Interrupt
;
98 SIGXCPU
: constant := 0; -- XCPU
99 SIGHUP
: constant := 1; -- hangup
100 SIGINT
: constant := 2; -- interrupt (rubout)
101 SIGQUIT
: constant := 3; -- quit (ASCD FS)
102 SIGILL
: constant := 4; -- illegal instruction (not reset)
103 SIGTRAP
: constant := 5; -- trace trap (not reset)
104 SIGIOT
: constant := 6; -- IOT instruction
105 SIGABRT
: constant := 6; -- used by abort, replace SIGIOT in the future
106 SIGEMT
: constant := 7; -- EMT instruction
107 SIGFPE
: constant := 8; -- floating point exception
108 SIGKILL
: constant := 9; -- kill (cannot be caught or ignored)
109 SIGBUS
: constant := 10; -- bus error
110 SIGSEGV
: constant := 11; -- segmentation violation
111 SIGSYS
: constant := 12; -- bad argument to system call
112 SIGPIPE
: constant := 13; -- write on a pipe with no one to read it
113 SIGALRM
: constant := 14; -- alarm clock
114 SIGTERM
: constant := 15; -- software termination signal from kill
115 SIGUSR1
: constant := 16; -- user defined signal 1
116 SIGUSR2
: constant := 17; -- user defined signal 2
118 SIGADAABORT
: constant := SIGABRT
;
120 type Signal_Set
is array (Natural range <>) of Signal
;
122 Unmasked
: constant Signal_Set
:= (SIGTRAP
, SIGALRM
, SIGEMT
);
123 Reserved
: constant Signal_Set
:= (1 .. 1 => SIGKILL
);
125 type sigset_t
is private;
127 function sigaddset
(set
: access sigset_t
; sig
: Signal
) return int
;
128 pragma Import
(C
, sigaddset
, "sigaddset");
130 function sigdelset
(set
: access sigset_t
; sig
: Signal
) return int
;
131 pragma Import
(C
, sigdelset
, "sigdelset");
133 function sigfillset
(set
: access sigset_t
) return int
;
134 pragma Import
(C
, sigfillset
, "sigfillset");
136 function sigismember
(set
: access sigset_t
; sig
: Signal
) return int
;
137 pragma Import
(C
, sigismember
, "sigismember");
139 function sigemptyset
(set
: access sigset_t
) return int
;
140 pragma Import
(C
, sigemptyset
, "sigemptyset");
142 type struct_sigaction
is record
145 sa_handler
: System
.Address
;
147 pragma Convention
(C
, struct_sigaction
);
148 type struct_sigaction_ptr
is access all struct_sigaction
;
150 SA_SIGINFO
: constant := 16#
02#
;
152 SA_ONSTACK
: constant := 16#
00#
;
153 -- SA_ONSTACK is not defined on RTEMS, but it is referred to in the POSIX
154 -- implementation of System.Interrupt_Management. Therefore we define a
155 -- dummy value of zero here so that setting this flag is a nop.
157 SIG_BLOCK
: constant := 1;
158 SIG_UNBLOCK
: constant := 2;
159 SIG_SETMASK
: constant := 3;
161 SIG_DFL
: constant := 0;
162 SIG_IGN
: constant := 1;
166 act
: struct_sigaction_ptr
;
167 oact
: struct_sigaction_ptr
) return int
;
168 pragma Import
(C
, sigaction
, "sigaction");
174 Time_Slice_Supported
: constant Boolean := True;
175 -- Indicates whether time slicing is supported (i.e SCHED_RR is supported)
177 type timespec
is private;
179 type clockid_t
is new int
;
181 CLOCK_REALTIME
: constant clockid_t
;
182 CLOCK_MONOTONIC
: constant clockid_t
;
184 function clock_gettime
185 (clock_id
: clockid_t
;
186 tp
: access timespec
) return int
;
187 pragma Import
(C
, clock_gettime
, "clock_gettime");
189 function To_Duration
(TS
: timespec
) return Duration;
190 pragma Inline
(To_Duration
);
192 function To_Timespec
(D
: Duration) return timespec
;
193 pragma Inline
(To_Timespec
);
195 -------------------------
196 -- Priority Scheduling --
197 -------------------------
199 SCHED_FIFO
: constant := 1;
200 SCHED_RR
: constant := 2;
201 SCHED_OTHER
: constant := 0;
203 function To_Target_Priority
204 (Prio
: System
.Any_Priority
) return Interfaces
.C
.int
;
205 -- Maps System.Any_Priority to a POSIX priority
211 type pid_t
is private;
213 function kill
(pid
: pid_t
; sig
: Signal
) return int
;
214 pragma Import
(C
, kill
, "kill");
216 function getpid
return pid_t
;
217 pragma Import
(C
, getpid
, "getpid");
223 function lwp_self
return System
.Address
;
224 -- lwp_self does not exist on this thread library, revert to pthread_self
225 -- which is the closest approximation (with getpid). This function is
226 -- needed to share 7staprop.adb across POSIX-like targets.
227 pragma Import
(C
, lwp_self
, "pthread_self");
233 type Thread_Body
is access
234 function (arg
: System
.Address
) return System
.Address
;
235 pragma Convention
(C
, Thread_Body
);
237 type pthread_t
is private;
238 subtype Thread_Id
is pthread_t
;
240 type pthread_mutex_t
is limited private;
241 type pthread_rwlock_t
is limited private;
242 type pthread_cond_t
is limited private;
243 type pthread_attr_t
is limited private;
244 type pthread_mutexattr_t
is limited private;
245 type pthread_rwlockattr_t
is limited private;
246 type pthread_condattr_t
is limited private;
247 type pthread_key_t
is private;
249 No_Key
: constant pthread_key_t
;
251 PTHREAD_CREATE_DETACHED
: constant := 0;
253 PTHREAD_SCOPE_PROCESS
: constant := 0;
254 PTHREAD_SCOPE_SYSTEM
: constant := 1;
260 type stack_t
is record
261 ss_sp
: System
.Address
;
265 pragma Convention
(C
, stack_t
);
268 (ss
: not null access stack_t
;
269 oss
: access stack_t
) return int
;
271 Alternate_Stack
: aliased System
.Address
;
272 -- This is a dummy definition, never used (Alternate_Stack_Size is null)
274 Alternate_Stack_Size
: constant := 0;
275 -- No alternate signal stack is used on this platform
277 Stack_Base_Available
: constant Boolean := False;
278 -- Indicates whether the stack base is available on this target.
279 -- This allows us to share s-osinte.adb between all the FSU/RTEMS
281 -- Note that this value can only be true if pthread_t has a complete
282 -- definition that corresponds exactly to the C header files.
284 function Get_Stack_Base
(thread
: pthread_t
) return Address
;
285 pragma Inline
(Get_Stack_Base
);
286 -- returns the stack base of the specified thread.
287 -- Only call this function when Stack_Base_Available is True.
289 -- These two functions are only needed to share s-taprop.adb with
292 function Get_Page_Size
return size_t
;
293 function Get_Page_Size
return Address
;
294 pragma Import
(C
, Get_Page_Size
, "getpagesize");
295 -- Returns the size of a page
297 PROT_ON
: constant := 0;
298 PROT_OFF
: constant := 0;
300 function mprotect
(addr
: Address
; len
: size_t
; prot
: int
) return int
;
301 pragma Import
(C
, mprotect
);
303 -----------------------------------------
304 -- Nonstandard Thread Initialization --
305 -----------------------------------------
307 procedure pthread_init
;
308 -- FSU_THREADS requires pthread_init, which is nonstandard
309 -- and this should be invoked during the elaboration of s-taprop.adb
311 -- RTEMS does not require this so we provide an empty Ada body.
313 -------------------------
314 -- POSIX.1c Section 3 --
315 -------------------------
318 (set
: access sigset_t
;
319 sig
: access Signal
) return int
;
320 pragma Import
(C
, sigwait
, "sigwait");
322 function pthread_kill
324 sig
: Signal
) return int
;
325 pragma Import
(C
, pthread_kill
, "pthread_kill");
327 function pthread_sigmask
329 set
: access sigset_t
;
330 oset
: access sigset_t
) return int
;
331 pragma Import
(C
, pthread_sigmask
, "pthread_sigmask");
333 ----------------------------
334 -- POSIX.1c Section 11 --
335 ----------------------------
337 function pthread_mutexattr_init
338 (attr
: access pthread_mutexattr_t
) return int
;
339 pragma Import
(C
, pthread_mutexattr_init
, "pthread_mutexattr_init");
341 function pthread_mutexattr_destroy
342 (attr
: access pthread_mutexattr_t
) return int
;
343 pragma Import
(C
, pthread_mutexattr_destroy
, "pthread_mutexattr_destroy");
345 function pthread_mutex_init
346 (mutex
: access pthread_mutex_t
;
347 attr
: access pthread_mutexattr_t
) return int
;
348 pragma Import
(C
, pthread_mutex_init
, "pthread_mutex_init");
350 function pthread_mutex_destroy
(mutex
: access pthread_mutex_t
) return int
;
351 pragma Import
(C
, pthread_mutex_destroy
, "pthread_mutex_destroy");
353 function pthread_mutex_lock
(mutex
: access pthread_mutex_t
) return int
;
354 pragma Import
(C
, pthread_mutex_lock
, "pthread_mutex_lock");
356 function pthread_mutex_unlock
(mutex
: access pthread_mutex_t
) return int
;
357 pragma Import
(C
, pthread_mutex_unlock
, "pthread_mutex_unlock");
359 function pthread_rwlockattr_init
360 (attr
: access pthread_rwlockattr_t
) return int
;
361 pragma Import
(C
, pthread_rwlockattr_init
, "pthread_rwlockattr_init");
363 function pthread_rwlockattr_destroy
364 (attr
: access pthread_rwlockattr_t
) return int
;
365 pragma Import
(C
, pthread_rwlockattr_destroy
, "pthread_rwlockattr_destroy");
367 PTHREAD_RWLOCK_PREFER_READER_NP
: constant := 0;
368 PTHREAD_RWLOCK_PREFER_WRITER_NP
: constant := 1;
369 PTHREAD_RWLOCK_PREFER_WRITER_NONRECURSIVE_NP
: constant := 2;
371 function pthread_rwlockattr_setkind_np
372 (attr
: access pthread_rwlockattr_t
;
373 pref
: int
) return int
;
375 function pthread_rwlock_init
376 (mutex
: access pthread_rwlock_t
;
377 attr
: access pthread_rwlockattr_t
) return int
;
378 pragma Import
(C
, pthread_rwlock_init
, "pthread_rwlock_init");
380 function pthread_rwlock_destroy
381 (mutex
: access pthread_rwlock_t
) return int
;
382 pragma Import
(C
, pthread_rwlock_destroy
, "pthread_rwlock_destroy");
384 function pthread_rwlock_rdlock
(mutex
: access pthread_rwlock_t
) return int
;
385 pragma Import
(C
, pthread_rwlock_rdlock
, "pthread_rwlock_rdlock");
387 function pthread_rwlock_wrlock
(mutex
: access pthread_rwlock_t
) return int
;
388 pragma Import
(C
, pthread_rwlock_wrlock
, "pthread_rwlock_wrlock");
390 function pthread_rwlock_unlock
(mutex
: access pthread_rwlock_t
) return int
;
391 pragma Import
(C
, pthread_rwlock_unlock
, "pthread_rwlock_unlock");
393 function pthread_condattr_init
394 (attr
: access pthread_condattr_t
) return int
;
395 pragma Import
(C
, pthread_condattr_init
, "pthread_condattr_init");
397 function pthread_condattr_destroy
398 (attr
: access pthread_condattr_t
) return int
;
399 pragma Import
(C
, pthread_condattr_destroy
, "pthread_condattr_destroy");
401 function pthread_cond_init
402 (cond
: access pthread_cond_t
;
403 attr
: access pthread_condattr_t
) return int
;
404 pragma Import
(C
, pthread_cond_init
, "pthread_cond_init");
406 function pthread_cond_destroy
(cond
: access pthread_cond_t
) return int
;
407 pragma Import
(C
, pthread_cond_destroy
, "pthread_cond_destroy");
409 function pthread_cond_signal
(cond
: access pthread_cond_t
) return int
;
410 pragma Import
(C
, pthread_cond_signal
, "pthread_cond_signal");
412 function pthread_cond_wait
413 (cond
: access pthread_cond_t
;
414 mutex
: access pthread_mutex_t
) return int
;
415 pragma Import
(C
, pthread_cond_wait
, "pthread_cond_wait");
417 function pthread_cond_timedwait
418 (cond
: access pthread_cond_t
;
419 mutex
: access pthread_mutex_t
;
420 abstime
: access timespec
) return int
;
421 pragma Import
(C
, pthread_cond_timedwait
, "pthread_cond_timedwait");
423 Relative_Timed_Wait
: constant Boolean := False;
424 -- pthread_cond_timedwait requires an absolute delay time
426 --------------------------
427 -- POSIX.1c Section 13 --
428 --------------------------
430 PTHREAD_PRIO_NONE
: constant := 0;
431 PTHREAD_PRIO_PROTECT
: constant := 2;
432 PTHREAD_PRIO_INHERIT
: constant := 1;
434 function pthread_mutexattr_setprotocol
435 (attr
: access pthread_mutexattr_t
;
436 protocol
: int
) return int
;
437 pragma Import
(C
, pthread_mutexattr_setprotocol
);
439 function pthread_mutexattr_setprioceiling
440 (attr
: access pthread_mutexattr_t
;
441 prioceiling
: int
) return int
;
443 (C
, pthread_mutexattr_setprioceiling
,
444 "pthread_mutexattr_setprioceiling");
446 type struct_sched_param
is record
447 sched_priority
: int
;
448 ss_low_priority
: int
;
449 ss_replenish_period
: timespec
;
450 ss_initial_budget
: timespec
;
452 pragma Convention
(C
, struct_sched_param
);
454 function pthread_setschedparam
457 param
: access struct_sched_param
) return int
;
458 pragma Import
(C
, pthread_setschedparam
, "pthread_setschedparam");
460 function pthread_attr_setscope
461 (attr
: access pthread_attr_t
;
462 contentionscope
: int
) return int
;
463 pragma Import
(C
, pthread_attr_setscope
, "pthread_attr_setscope");
465 function pthread_attr_setinheritsched
466 (attr
: access pthread_attr_t
;
467 inheritsched
: int
) return int
;
468 pragma Import
(C
, pthread_attr_setinheritsched
);
470 function pthread_attr_setschedpolicy
471 (attr
: access pthread_attr_t
;
472 policy
: int
) return int
;
473 pragma Import
(C
, pthread_attr_setschedpolicy
);
475 function pthread_attr_setschedparam
476 (attr
: access pthread_attr_t
;
477 sched_param
: int
) return int
;
478 pragma Import
(C
, pthread_attr_setschedparam
);
480 function sched_yield
return int
;
481 pragma Import
(C
, sched_yield
, "sched_yield");
483 ---------------------------
484 -- P1003.1c - Section 16 --
485 ---------------------------
487 function pthread_attr_init
(attributes
: access pthread_attr_t
) return int
;
488 pragma Import
(C
, pthread_attr_init
, "pthread_attr_init");
490 function pthread_attr_destroy
491 (attributes
: access pthread_attr_t
) return int
;
492 pragma Import
(C
, pthread_attr_destroy
, "pthread_attr_destroy");
494 function pthread_attr_setdetachstate
495 (attr
: access pthread_attr_t
;
496 detachstate
: int
) return int
;
497 pragma Import
(C
, pthread_attr_setdetachstate
);
499 function pthread_attr_setstacksize
500 (attr
: access pthread_attr_t
;
501 stacksize
: size_t
) return int
;
502 pragma Import
(C
, pthread_attr_setstacksize
, "pthread_attr_setstacksize");
504 function pthread_create
505 (thread
: access pthread_t
;
506 attributes
: access pthread_attr_t
;
507 start_routine
: Thread_Body
;
508 arg
: System
.Address
) return int
;
509 pragma Import
(C
, pthread_create
, "pthread_create");
511 procedure pthread_exit
(status
: System
.Address
);
512 pragma Import
(C
, pthread_exit
, "pthread_exit");
514 function pthread_self
return pthread_t
;
515 pragma Import
(C
, pthread_self
, "pthread_self");
517 --------------------------
518 -- POSIX.1c Section 17 --
519 --------------------------
521 function pthread_setspecific
522 (key
: pthread_key_t
;
523 value
: System
.Address
) return int
;
524 pragma Import
(C
, pthread_setspecific
, "pthread_setspecific");
526 function pthread_getspecific
(key
: pthread_key_t
) return System
.Address
;
527 pragma Import
(C
, pthread_getspecific
, "pthread_getspecific");
529 type destructor_pointer
is access procedure (arg
: System
.Address
);
530 pragma Convention
(C
, destructor_pointer
);
532 function pthread_key_create
533 (key
: access pthread_key_t
;
534 destructor
: destructor_pointer
) return int
;
535 pragma Import
(C
, pthread_key_create
, "pthread_key_create");
537 ------------------------------------------------------------
538 -- Binary Semaphore Wrapper to Support Interrupt Tasks --
539 ------------------------------------------------------------
541 type Binary_Semaphore_Id
is new rtems_id
;
543 function Binary_Semaphore_Create
return Binary_Semaphore_Id
;
546 Binary_Semaphore_Create
,
547 "__gnat_binary_semaphore_create");
549 function Binary_Semaphore_Delete
(ID
: Binary_Semaphore_Id
) return int
;
552 Binary_Semaphore_Delete
,
553 "__gnat_binary_semaphore_delete");
555 function Binary_Semaphore_Obtain
(ID
: Binary_Semaphore_Id
) return int
;
558 Binary_Semaphore_Obtain
,
559 "__gnat_binary_semaphore_obtain");
561 function Binary_Semaphore_Release
(ID
: Binary_Semaphore_Id
) return int
;
564 Binary_Semaphore_Release
,
565 "__gnat_binary_semaphore_release");
567 function Binary_Semaphore_Flush
(ID
: Binary_Semaphore_Id
) return int
;
570 Binary_Semaphore_Flush
,
571 "__gnat_binary_semaphore_flush");
573 ------------------------------------------------------------
574 -- Hardware Interrupt Wrappers to Support Interrupt Tasks --
575 ------------------------------------------------------------
577 type Interrupt_Handler
is access procedure (parameter
: System
.Address
);
578 pragma Convention
(C
, Interrupt_Handler
);
579 type Interrupt_Vector
is new System
.Address
;
581 function Interrupt_Connect
582 (vector
: Interrupt_Vector
;
583 handler
: Interrupt_Handler
;
584 parameter
: System
.Address
:= System
.Null_Address
) return int
;
585 pragma Import
(C
, Interrupt_Connect
, "__gnat_interrupt_connect");
586 -- Use this to set up an user handler. The routine installs a
587 -- a user handler which is invoked after RTEMS has saved enough
588 -- context for a high-level language routine to be safely invoked.
590 function Interrupt_Vector_Get
591 (Vector
: Interrupt_Vector
) return Interrupt_Handler
;
592 pragma Import
(C
, Interrupt_Vector_Get
, "__gnat_interrupt_get");
593 -- Use this to get the existing handler for later restoral.
595 procedure Interrupt_Vector_Set
596 (Vector
: Interrupt_Vector
;
597 Handler
: Interrupt_Handler
);
598 pragma Import
(C
, Interrupt_Vector_Set
, "__gnat_interrupt_set");
599 -- Use this to restore a handler obtained using Interrupt_Vector_Get.
601 function Interrupt_Number_To_Vector
(intNum
: int
) return Interrupt_Vector
;
602 -- Convert a logical interrupt number to the hardware interrupt vector
603 -- number used to connect the interrupt.
606 Interrupt_Number_To_Vector
,
607 "__gnat_interrupt_number_to_vector"
612 type sigset_t
is new int
;
614 type pid_t
is new int
;
616 type time_t
is new long
;
618 type timespec
is record
622 pragma Convention
(C
, timespec
);
624 CLOCK_REALTIME
: constant clockid_t
:= 1;
625 CLOCK_MONOTONIC
: constant clockid_t
:= 4;
627 type pthread_attr_t
is record
628 is_initialized
: int
;
629 stackaddr
: System
.Address
;
631 contentionscope
: int
;
634 schedparam
: struct_sched_param
;
635 cputime_clocked_allowed
: int
;
638 pragma Convention
(C
, pthread_attr_t
);
640 type pthread_condattr_t
is record
642 process_shared
: int
;
644 pragma Convention
(C
, pthread_condattr_t
);
646 type pthread_mutexattr_t
is record
647 is_initialized
: int
;
648 process_shared
: int
;
654 pragma Convention
(C
, pthread_mutexattr_t
);
656 type pthread_rwlockattr_t
is record
657 is_initialized
: int
;
658 process_shared
: int
;
660 pragma Convention
(C
, pthread_rwlockattr_t
);
662 type pthread_t
is new rtems_id
;
664 type pthread_mutex_t
is new rtems_id
;
666 type pthread_rwlock_t
is new rtems_id
;
668 type pthread_cond_t
is new rtems_id
;
670 type pthread_key_t
is new rtems_id
;
672 No_Key
: constant pthread_key_t
:= 0;
674 end System
.OS_Interface
;