1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
5 -- S Y S T E M . O S _ L I B --
9 -- Copyright (C) 1995-2009, Free Software Foundation, Inc. --
11 -- GNAT 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 -- GNAT was originally developed by the GNAT team at New York University. --
28 -- Extensive contributions were provided by Ada Core Technologies Inc. --
30 ------------------------------------------------------------------------------
32 -- Operating system interface facilities
34 -- This package contains types and procedures for interfacing to the
35 -- underlying OS. It is used by the GNAT compiler and by tools associated
36 -- with the GNAT compiler, and therefore works for the various operating
37 -- systems to which GNAT has been ported. This package will undoubtedly grow
38 -- as new services are needed by various tools.
40 -- This package tends to use fairly low-level Ada in order to not bring in
41 -- large portions of the RTL. For example, functions return access to string
42 -- as part of avoiding functions returning unconstrained types.
44 -- Except where specifically noted, these routines are portable across all
45 -- GNAT implementations on all supported operating systems.
47 -- Note: this package is in the System hierarchy so that it can be directly
48 -- be used by other predefined packages. User access to this package is via
49 -- a renaming of this package in GNAT.OS_Lib (file g-os_lib.ads).
51 pragma Warnings (Off);
58 package System.OS_Lib is
59 pragma Elaborate_Body (OS_Lib);
61 -----------------------
62 -- String Operations --
63 -----------------------
65 -- These are reexported from package Strings (which was introduced to
66 -- avoid different packages declaring different types unnecessarily).
67 -- See package System.Strings for details.
69 subtype String_Access is Strings.String_Access;
71 function "=" (Left, Right : String_Access) return Boolean
74 procedure Free (X : in out String_Access) renames Strings.Free;
76 subtype String_List is Strings.String_List;
78 function "=" (Left, Right : String_List) return Boolean
81 function "&" (Left : String_Access; Right : String_Access)
82 return String_List renames Strings."&";
83 function "&" (Left : String_Access; Right : String_List)
84 return String_List renames Strings."&";
85 function "&" (Left : String_List; Right : String_Access)
86 return String_List renames Strings."&";
87 function "&" (Left : String_List; Right : String_List)
88 return String_List renames Strings."&";
90 subtype String_List_Access is Strings.String_List_Access;
92 function "=" (Left, Right : String_List_Access) return Boolean
95 procedure Free (Arg : in out String_List_Access)
100 ---------------------
102 type OS_Time is private;
103 -- The OS's notion of time is represented by the private type OS_Time.
104 -- This is the type returned by the File_Time_Stamp functions to obtain
105 -- the time stamp of a specified file. Functions and a procedure (modeled
106 -- after the similar subprograms in package Calendar) are provided for
107 -- extracting information from a value of this type. Although these are
108 -- called GM, the intention is not that they provide GMT times in all
109 -- cases but rather the actual (time-zone independent) time stamp of the
110 -- file (of course in Unix systems, this *is* in GMT form).
112 Invalid_Time : constant OS_Time;
113 -- A special unique value used to flag an invalid time stamp value
115 subtype Year_Type is Integer range 1900 .. 2099;
116 subtype Month_Type is Integer range 1 .. 12;
117 subtype Day_Type is Integer range 1 .. 31;
118 subtype Hour_Type is Integer range 0 .. 23;
119 subtype Minute_Type is Integer range 0 .. 59;
120 subtype Second_Type is Integer range 0 .. 59;
121 -- Declarations similar to those in Calendar, breaking down the time
123 function Current_Time return OS_Time;
124 -- Return the system clock value as OS_Time
126 function GM_Year (Date : OS_Time) return Year_Type;
127 function GM_Month (Date : OS_Time) return Month_Type;
128 function GM_Day (Date : OS_Time) return Day_Type;
129 function GM_Hour (Date : OS_Time) return Hour_Type;
130 function GM_Minute (Date : OS_Time) return Minute_Type;
131 function GM_Second (Date : OS_Time) return Second_Type;
132 -- Functions to extract information from OS_Time value
134 function "<" (X, Y : OS_Time) return Boolean;
135 function ">" (X, Y : OS_Time) return Boolean;
136 function ">=" (X, Y : OS_Time) return Boolean;
137 function "<=" (X, Y : OS_Time) return Boolean;
138 -- Basic comparison operators on OS_Time with obvious meanings. Note that
139 -- these have Intrinsic convention, so for example it is not permissible
140 -- to create accesses to any of these functions.
144 Year : out Year_Type;
145 Month : out Month_Type;
147 Hour : out Hour_Type;
148 Minute : out Minute_Type;
149 Second : out Second_Type);
150 -- Analogous to the Split routine in Ada.Calendar, takes an OS_Time and
151 -- provides a representation of it as a set of component parts, to be
152 -- interpreted as a date point in UTC.
158 -- These routines give access to the open/creat/close/read/write level of
159 -- I/O routines in the typical C library (these functions are not part of
160 -- the ANSI C standard, but are typically available in all systems). See
161 -- also package Interfaces.C_Streams for access to the stream level
164 -- Note on file names. If a file name is passed as type String in any of
165 -- the following specifications, then the name is a normal Ada string and
166 -- need not be NUL-terminated. However, a trailing NUL character is
167 -- permitted, and will be ignored (more accurately, the NUL and any
168 -- characters that follow it will be ignored).
170 type File_Descriptor is new Integer;
171 -- Corresponds to the int file handle values used in the C routines
173 Standin : constant File_Descriptor := 0;
174 Standout : constant File_Descriptor := 1;
175 Standerr : constant File_Descriptor := 2;
176 -- File descriptors for standard input output files
178 Invalid_FD : constant File_Descriptor := -1;
179 -- File descriptor returned when error in opening/creating file;
181 type Mode is (Binary, Text);
182 for Mode'Size use Integer'Size;
183 for Mode use (Binary => 0, Text => 1);
184 -- Used in all the Open and Create calls to specify if the file is to be
185 -- opened in binary mode or text mode. In systems like Unix, this has no
186 -- effect, but in systems capable of text mode translation, the use of
187 -- Text as the mode parameter causes the system to do CR/LF translation
188 -- and also to recognize the DOS end of file character on input. The use
189 -- of Text where appropriate allows programs to take a portable Unix view
190 -- of DOS-format files and process them appropriately.
194 Fmode : Mode) return File_Descriptor;
195 -- Open file Name for reading, returning file descriptor File descriptor
196 -- returned is Invalid_FD if file cannot be opened.
198 function Open_Read_Write
200 Fmode : Mode) return File_Descriptor;
201 -- Open file Name for both reading and writing, returning file descriptor.
202 -- File descriptor returned is Invalid_FD if file cannot be opened.
206 Fmode : Mode) return File_Descriptor;
207 -- Creates new file with given name for writing, returning file descriptor
208 -- for subsequent use in Write calls. File descriptor returned is
209 -- Invalid_FD if file cannot be successfully created.
211 function Create_Output_Text_File (Name : String) return File_Descriptor;
212 -- Creates new text file with given name suitable to redirect standard
213 -- output, returning file descriptor. File descriptor returned is
214 -- Invalid_FD if file cannot be successfully created.
216 function Create_New_File
218 Fmode : Mode) return File_Descriptor;
219 -- Create new file with given name for writing, returning file descriptor
220 -- for subsequent use in Write calls. This differs from Create_File in
221 -- that it fails if the file already exists. File descriptor returned is
222 -- Invalid_FD if the file exists or cannot be created.
224 Temp_File_Len : constant Integer := 12;
225 -- Length of name returned by Create_Temp_File call (GNAT-XXXXXX & NUL)
227 subtype Temp_File_Name is String (1 .. Temp_File_Len);
228 -- String subtype set by Create_Temp_File
230 procedure Create_Temp_File
231 (FD : out File_Descriptor;
232 Name : out Temp_File_Name);
233 -- Create and open for writing a temporary file in the current working
234 -- directory. The name of the file and the File Descriptor are returned.
235 -- The File Descriptor returned is Invalid_FD in the case of failure. No
236 -- mode parameter is provided. Since this is a temporary file, there is no
237 -- point in doing text translation on it.
239 -- On some operating systems, the maximum number of temp files that can be
240 -- created with this procedure may be limited. When the maximum is reached,
241 -- this procedure returns Invalid_FD. On some operating systems, there may
242 -- be a race condition between processes trying to create temp files at the
243 -- same time in the same directory using this procedure.
245 procedure Create_Temp_File
246 (FD : out File_Descriptor;
247 Name : out String_Access);
248 -- Create and open for writing a temporary file in the current working
249 -- directory. The name of the file and the File Descriptor are returned.
250 -- No mode parameter is provided. Since this is a temporary file, there is
251 -- no point in doing text translation on it. It is the responsibility of
252 -- the caller to deallocate the access value returned in Name.
254 -- This procedure will always succeed if the current working directory is
255 -- writable. If the current working directory is not writable, then
256 -- Invalid_FD is returned for the file descriptor and null for the Name.
257 -- There is no race condition problem between processes trying to create
258 -- temp files at the same time in the same directory.
260 procedure Close (FD : File_Descriptor; Status : out Boolean);
261 -- Close file referenced by FD. Status is False if the underlying service
262 -- failed. Reasons for failure include: disk full, disk quotas exceeded
263 -- and invalid file descriptor (the file may have been closed twice).
265 procedure Close (FD : File_Descriptor);
266 -- Close file referenced by FD. This form is used when the caller wants to
267 -- ignore any possible error (see above for error cases).
269 procedure Set_Close_On_Exec
270 (FD : File_Descriptor;
271 Close_On_Exec : Boolean;
272 Status : out Boolean);
273 -- When Close_On_Exec is True, mark FD to be closed automatically when new
274 -- program is executed by the calling process (i.e. prevent FD from being
275 -- inherited by child processes). When Close_On_Exec is False, mark FD to
276 -- not be closed on exec (i.e. allow it to be inherited). Status is False
277 -- if the operation could not be performed.
279 procedure Delete_File (Name : String; Success : out Boolean);
280 -- Deletes file. Success is set True or False indicating if the delete is
283 procedure Rename_File
286 Success : out Boolean);
287 -- Rename a file. Success is set True or False indicating if the rename is
288 -- successful or not.
290 -- The following defines the mode for the Copy_File procedure below. Note
291 -- that "time stamps and other file attributes" in the descriptions below
292 -- refers to the creation and last modification times, and also the file
293 -- access (read/write/execute) status flags.
297 -- Copy the file. It is an error if the target file already exists. The
298 -- time stamps and other file attributes are preserved in the copy.
301 -- If the target file exists, the file is replaced otherwise the file
302 -- is just copied. The time stamps and other file attributes are
303 -- preserved in the copy.
306 -- If the target file exists, the contents of the source file is
307 -- appended at the end. Otherwise the source file is just copied. The
308 -- time stamps and other file attributes are preserved if the
309 -- destination file does not exist.
313 -- Copy time stamps from source file to target file. All other
314 -- attributes are set to normal default values for file creation.
317 -- All attributes are copied from the source file to the target file.
318 -- This includes the timestamps, and for example also includes
319 -- read/write/execute attributes in Unix systems.
322 -- No attributes are copied. All attributes including the time stamp
323 -- values are set to normal default values for file creation.
325 -- Note: The default is Time_Stamps, which corresponds to the normal
326 -- default on Windows style systems. Full corresponds to the typical
327 -- effect of "cp -p" on Unix systems, and None corresponds to the typical
328 -- effect of "cp" on Unix systems.
330 -- Note: Time_Stamps and Full are not supported on VMS and VxWorks
335 Success : out Boolean;
336 Mode : Copy_Mode := Copy;
337 Preserve : Attribute := Time_Stamps);
338 -- Copy a file. Name must designate a single file (no wild cards allowed).
339 -- Pathname can be a filename or directory name. In the latter case Name
340 -- is copied into the directory preserving the same file name. Mode
341 -- defines the kind of copy, see above with the default being a normal
342 -- copy in which the target file must not already exist. Success is set to
343 -- True or False indicating if the copy is successful (depending on the
346 -- Note: this procedure is only supported to a very limited extent on VMS.
347 -- The only supported mode is Overwrite, and the only supported value for
348 -- Preserve is None, resulting in the default action which for Overwrite
349 -- is to leave attributes unchanged. Furthermore, the copy only works for
350 -- simple text files.
352 procedure Copy_Time_Stamps (Source, Dest : String; Success : out Boolean);
353 -- Copy Source file time stamps (last modification and last access time
354 -- stamps) to Dest file. Source and Dest must be valid filenames,
355 -- furthermore Dest must be writable. Success will be set to True if the
356 -- operation was successful and False otherwise.
358 -- Note: this procedure is not supported on VMS and VxWorks. On these
359 -- platforms, Success is always set to False.
362 (FD : File_Descriptor;
364 N : Integer) return Integer;
365 -- Read N bytes to address A from file referenced by FD. Returned value is
366 -- count of bytes actually read, which can be less than N at EOF.
369 (FD : File_Descriptor;
371 N : Integer) return Integer;
372 -- Write N bytes from address A to file referenced by FD. The returned
373 -- value is the number of bytes written, which can be less than N if a
374 -- disk full condition was detected.
376 Seek_Cur : constant := 1;
377 Seek_End : constant := 2;
378 Seek_Set : constant := 0;
379 -- Used to indicate origin for Lseek call
382 (FD : File_Descriptor;
383 offset : Long_Integer;
385 pragma Import (C, Lseek, "__gnat_lseek");
386 -- Sets the current file pointer to the indicated offset value, relative
387 -- to the current position (origin = SEEK_CUR), end of file (origin =
388 -- SEEK_END), or start of file (origin = SEEK_SET).
390 function File_Length (FD : File_Descriptor) return Long_Integer;
391 pragma Import (C, File_Length, "__gnat_file_length");
392 -- Get length of file from file descriptor FD
394 function File_Time_Stamp (Name : String) return OS_Time;
395 -- Given the name of a file or directory, Name, obtains and returns the
396 -- time stamp. This function can be used for an unopened file. Returns
397 -- Invalid_Time is Name doesn't correspond to an existing file.
399 function File_Time_Stamp (FD : File_Descriptor) return OS_Time;
400 -- Get time stamp of file from file descriptor FD Returns Invalid_Time is
401 -- FD doesn't correspond to an existing file.
403 function Normalize_Pathname
405 Directory : String := "";
406 Resolve_Links : Boolean := True;
407 Case_Sensitive : Boolean := True) return String;
408 -- Returns a file name as an absolute path name, resolving all relative
409 -- directories, and symbolic links. The parameter Directory is a fully
410 -- resolved path name for a directory, or the empty string (the default).
411 -- Name is the name of a file, which is either relative to the given
412 -- directory name, if Directory is non-null, or to the current working
413 -- directory if Directory is null. The result returned is the normalized
414 -- name of the file. For most cases, if two file names designate the same
415 -- file through different paths, Normalize_Pathname will return the same
416 -- canonical name in both cases. However, there are cases when this is not
417 -- true; for example, this is not true in Unix for two hard links
418 -- designating the same file.
420 -- On Windows, the returned path will start with a drive letter except
421 -- when Directory is not empty and does not include a drive letter. If
422 -- Directory is empty (the default) and Name is a relative path or an
423 -- absolute path without drive letter, the letter of the current drive
424 -- will start the returned path. If Case_Sensitive is True (the default),
425 -- then this drive letter will be forced to upper case ("C:\...").
427 -- If Resolve_Links is set to True, then the symbolic links, on systems
428 -- that support them, will be fully converted to the name of the file or
429 -- directory pointed to. This is slightly less efficient, since it
430 -- requires system calls.
432 -- If Name cannot be resolved or is null on entry (for example if there is
433 -- symbolic link circularity, e.g. A is a symbolic link for B, and B is a
434 -- symbolic link for A), then Normalize_Pathname returns an empty string.
436 -- In VMS, if Name follows the VMS syntax file specification, it is first
437 -- converted into Unix syntax. If the conversion fails, Normalize_Pathname
438 -- returns an empty string.
440 -- For case-sensitive file systems, the value of Case_Sensitive parameter
441 -- is ignored. For file systems that are not case-sensitive, such as
442 -- Windows and OpenVMS, if this parameter is set to False, then the file
443 -- and directory names are folded to lower case. This allows checking
444 -- whether two files are the same by applying this function to their names
445 -- and comparing the results. If Case_Sensitive is set to True, this
446 -- function does not change the casing of file and directory names.
448 function Is_Absolute_Path (Name : String) return Boolean;
449 -- Returns True if Name is an absolute path name, i.e. it designates a
450 -- file or directory absolutely rather than relative to another directory.
452 function Is_Regular_File (Name : String) return Boolean;
453 -- Determines if the given string, Name, is the name of an existing
454 -- regular file. Returns True if so, False otherwise. Name may be an
455 -- absolute path name or a relative path name, including a simple file
456 -- name. If it is a relative path name, it is relative to the current
457 -- working directory.
459 function Is_Directory (Name : String) return Boolean;
460 -- Determines if the given string, Name, is the name of a directory.
461 -- Returns True if so, False otherwise. Name may be an absolute path
462 -- name or a relative path name, including a simple file name. If it is
463 -- a relative path name, it is relative to the current working directory.
465 function Is_Readable_File (Name : String) return Boolean;
466 -- Determines if the given string, Name, is the name of an existing file
467 -- that is readable. Returns True if so, False otherwise. Note that this
468 -- function simply interrogates the file attributes (e.g. using the C
469 -- function stat), so it does not indicate a situation in which a file may
470 -- not actually be readable due to some other process having exclusive
473 function Is_Executable_File (Name : String) return Boolean;
474 -- Determines if the given string, Name, is the name of an existing file
475 -- that is executable. Returns True if so, False otherwise. Note that this
476 -- function simply interrogates the file attributes (e.g. using the C
477 -- function stat), so it does not indicate a situation in which a file may
478 -- not actually be readable due to some other process having exclusive
481 function Is_Writable_File (Name : String) return Boolean;
482 -- Determines if the given string, Name, is the name of an existing file
483 -- that is writable. Returns True if so, False otherwise. Note that this
484 -- function simply interrogates the file attributes (e.g. using the C
485 -- function stat), so it does not indicate a situation in which a file may
486 -- not actually be writeable due to some other process having exclusive
489 function Is_Symbolic_Link (Name : String) return Boolean;
490 -- Determines if the given string, Name, is the path of a symbolic link on
491 -- systems that support it. Returns True if so, False if the path is not a
492 -- symbolic link or if the system does not support symbolic links.
494 -- A symbolic link is an indirect pointer to a file; its directory entry
495 -- contains the name of the file to which it is linked. Symbolic links may
496 -- span file systems and may refer to directories.
498 procedure Set_Writable (Name : String);
499 -- Change permissions on the named file to make it writable for its owner
501 procedure Set_Non_Writable (Name : String);
502 -- Change permissions on the named file to make it non-writable for its
503 -- owner. The readable and executable permissions are not modified.
505 procedure Set_Read_Only (Name : String) renames Set_Non_Writable;
506 -- This renaming is provided for backwards compatibility with previous
507 -- versions. The use of Set_Non_Writable is preferred (clearer name).
509 procedure Set_Executable (Name : String);
510 -- Change permissions on the named file to make it executable for its owner
512 procedure Set_Readable (Name : String);
513 -- Change permissions on the named file to make it readable for its
516 procedure Set_Non_Readable (Name : String);
517 -- Change permissions on the named file to make it non-readable for
518 -- its owner. The writable and executable permissions are not
521 function Locate_Exec_On_Path
522 (Exec_Name : String) return String_Access;
523 -- Try to locate an executable whose name is given by Exec_Name in the
524 -- directories listed in the environment Path. If the Exec_Name does not
525 -- have the executable suffix, it will be appended before the search.
526 -- Otherwise works like Locate_Regular_File below. If the executable is
527 -- not found, null is returned.
529 -- Note that this function allocates memory for the returned value. This
530 -- memory needs to be deallocated after use.
532 function Locate_Regular_File
534 Path : String) return String_Access;
535 -- Try to locate a regular file whose name is given by File_Name in the
536 -- directories listed in Path. If a file is found, its full pathname is
537 -- returned; otherwise, a null pointer is returned. If the File_Name given
538 -- is an absolute pathname, then Locate_Regular_File just checks that the
539 -- file exists and is a regular file. Otherwise, if the File_Name given
540 -- includes directory information, Locate_Regular_File first checks if the
541 -- file exists relative to the current directory. If it does not, or if
542 -- the File_Name given is a simple file name, the Path argument is parsed
543 -- according to OS conventions, and for each directory in the Path a check
544 -- is made if File_Name is a relative pathname of a regular file from that
547 -- Note that this function allocates some memory for the returned value.
548 -- This memory needs to be deallocated after use.
550 function Get_Debuggable_Suffix return String_Access;
551 -- Return the debuggable suffix convention. Usually this is the same as
552 -- the convention for Get_Executable_Suffix. The result is allocated on
553 -- the heap and should be freed after use to avoid storage leaks.
555 function Get_Target_Debuggable_Suffix return String_Access;
556 -- Return the target debuggable suffix convention. Usually this is the same
557 -- as the convention for Get_Executable_Suffix. The result is allocated on
558 -- the heap and should be freed after use to avoid storage leaks.
560 function Get_Executable_Suffix return String_Access;
561 -- Return the executable suffix convention. The result is allocated on the
562 -- heap and should be freed after use to avoid storage leaks.
564 function Get_Object_Suffix return String_Access;
565 -- Return the object suffix convention. The result is allocated on the heap
566 -- and should be freed after use to avoid storage leaks.
568 function Get_Target_Executable_Suffix return String_Access;
569 -- Return the target executable suffix convention. The result is allocated
570 -- on the heap and should be freed after use to avoid storage leaks.
572 function Get_Target_Object_Suffix return String_Access;
573 -- Return the target object suffix convention. The result is allocated on
574 -- the heap and should be freed after use to avoid storage leaks.
576 -- The following section contains low-level routines using addresses to
577 -- pass file name and executable name. In each routine the name must be
578 -- Nul-Terminated. For complete documentation refer to the equivalent
579 -- routine (using String in place of C_File_Name) defined above.
581 subtype C_File_Name is System.Address;
582 -- This subtype is used to document that a parameter is the address of a
583 -- null-terminated string containing the name of a file.
585 -- All the following functions need comments ???
589 Fmode : Mode) return File_Descriptor;
591 function Open_Read_Write
593 Fmode : Mode) return File_Descriptor;
597 Fmode : Mode) return File_Descriptor;
599 function Create_New_File
601 Fmode : Mode) return File_Descriptor;
603 procedure Delete_File (Name : C_File_Name; Success : out Boolean);
605 procedure Rename_File
606 (Old_Name : C_File_Name;
607 New_Name : C_File_Name;
608 Success : out Boolean);
612 Pathname : C_File_Name;
613 Success : out Boolean;
614 Mode : Copy_Mode := Copy;
615 Preserve : Attribute := Time_Stamps);
617 procedure Copy_Time_Stamps
618 (Source, Dest : C_File_Name;
619 Success : out Boolean);
621 function File_Time_Stamp (Name : C_File_Name) return OS_Time;
622 -- Returns Invalid_Time is Name doesn't correspond to an existing file
624 function Is_Regular_File (Name : C_File_Name) return Boolean;
625 function Is_Directory (Name : C_File_Name) return Boolean;
626 function Is_Readable_File (Name : C_File_Name) return Boolean;
627 function Is_Executable_File (Name : C_File_Name) return Boolean;
628 function Is_Writable_File (Name : C_File_Name) return Boolean;
629 function Is_Symbolic_Link (Name : C_File_Name) return Boolean;
631 function Locate_Regular_File
632 (File_Name : C_File_Name;
633 Path : C_File_Name) return String_Access;
639 subtype Argument_List is String_List;
640 -- Type used for argument list in call to Spawn. The lower bound of the
641 -- array should be 1, and the length of the array indicates the number of
644 subtype Argument_List_Access is String_List_Access;
645 -- Type used to return Argument_List without dragging in secondary stack.
646 -- Note that there is a Free procedure declared for this subtype which
647 -- frees the array and all referenced strings.
649 procedure Normalize_Arguments (Args : in out Argument_List);
650 -- Normalize all arguments in the list. This ensure that the argument list
651 -- is compatible with the running OS and will works fine with Spawn and
652 -- Non_Blocking_Spawn for example. If Normalize_Arguments is called twice
653 -- on the same list it will do nothing the second time. Note that Spawn
654 -- and Non_Blocking_Spawn call Normalize_Arguments automatically, but
655 -- since there is a guarantee that a second call does nothing, this
656 -- internal call will have no effect if Normalize_Arguments is called
657 -- before calling Spawn. The call to Normalize_Arguments assumes that the
658 -- individual referenced arguments in Argument_List are on the heap, and
659 -- may free them and reallocate if they are modified.
662 (Program_Name : String;
663 Args : Argument_List;
664 Success : out Boolean);
665 -- This procedure spawns a program with a given list of arguments. The
666 -- first parameter of is the name of the executable. The second parameter
667 -- contains the arguments to be passed to this program. Success is False
668 -- if the named program could not be spawned or its execution completed
669 -- unsuccessfully. Note that the caller will be blocked until the
670 -- execution of the spawned program is complete. For maximum portability,
671 -- use a full path name for the Program_Name argument. On some systems
672 -- (notably Unix systems) a simple file name may also work (if the
673 -- executable can be located in the path).
675 -- "Spawn" should be avoided in tasking applications, since there are
676 -- subtle interactions between creating a process and signals/locks
677 -- that can cause troubles.
679 -- Note: Arguments in Args that contain spaces and/or quotes such as
680 -- "--GCC=gcc -v" or "--GCC=""gcc -v""" are not portable across all
681 -- operating systems, and would not have the desired effect if they were
682 -- passed directly to the operating system. To avoid this problem, Spawn
683 -- makes an internal call to Normalize_Arguments, which ensures that such
684 -- arguments are modified in a manner that ensures that the desired effect
685 -- is obtained on all operating systems. The caller may call
686 -- Normalize_Arguments explicitly before the call (e.g. to print out the
687 -- exact form of arguments passed to the operating system). In this case
688 -- the guarantee a second call to Normalize_Arguments has no effect
689 -- ensures that the internal call will not affect the result. Note that
690 -- the implicit call to Normalize_Arguments may free and reallocate some
691 -- of the individual arguments.
693 -- This function will always set Success to False under VxWorks and other
694 -- similar operating systems which have no notion of the concept of
695 -- dynamically executable file.
698 (Program_Name : String;
699 Args : Argument_List) return Integer;
700 -- Similar to the above procedure, but returns the actual status returned
701 -- by the operating system, or -1 under VxWorks and any other similar
702 -- operating systems which have no notion of separately spawnable programs.
704 -- "Spawn" should not be used in tasking applications.
707 (Program_Name : String;
708 Args : Argument_List;
709 Output_File_Descriptor : File_Descriptor;
710 Return_Code : out Integer;
711 Err_To_Out : Boolean := True);
712 -- Similar to the procedure above, but redirects the output to the file
713 -- designated by Output_File_Descriptor. If Err_To_Out is True, then the
714 -- Standard Error output is also redirected.
715 -- Return_Code is set to the status code returned by the operating system
717 -- "Spawn" should not be used in tasking applications.
720 (Program_Name : String;
721 Args : Argument_List;
722 Output_File : String;
723 Success : out Boolean;
724 Return_Code : out Integer;
725 Err_To_Out : Boolean := True);
726 -- Similar to the procedure above, but saves the output of the command to
727 -- a file with the name Output_File.
729 -- Success is set to True if the command is executed and its output
730 -- successfully written to the file. If Success is True, then Return_Code
731 -- will be set to the status code returned by the operating system.
732 -- Otherwise, Return_Code is undefined.
734 -- "Spawn" should not be used in tasking applications.
736 type Process_Id is private;
737 -- A private type used to identify a process activated by the following
738 -- non-blocking calls. The only meaningful operation on this type is a
739 -- comparison for equality.
741 Invalid_Pid : constant Process_Id;
742 -- A special value used to indicate errors, as described below
744 function Pid_To_Integer (Pid : Process_Id) return Integer;
745 -- Convert a process id to an Integer. Useful for writing hash functions
746 -- for type Process_Id or to compare two Process_Id (e.g. for sorting).
748 function Non_Blocking_Spawn
749 (Program_Name : String;
750 Args : Argument_List) return Process_Id;
751 -- This is a non blocking call. The Process_Id of the spawned process is
752 -- returned. Parameters are to be used as in Spawn. If Invalid_Pid is
753 -- returned the program could not be spawned.
755 -- "Non_Blocking_Spawn" should not be used in tasking applications.
757 -- This function will always return Invalid_Pid under VxWorks, since there
758 -- is no notion of executables under this OS.
760 function Non_Blocking_Spawn
761 (Program_Name : String;
762 Args : Argument_List;
763 Output_File_Descriptor : File_Descriptor;
764 Err_To_Out : Boolean := True) return Process_Id;
765 -- Similar to the procedure above, but redirects the output to the file
766 -- designated by Output_File_Descriptor. If Err_To_Out is True, then the
767 -- Standard Error output is also redirected. Invalid_Pid is returned
768 -- if the program could not be spawned successfully.
770 -- "Non_Blocking_Spawn" should not be used in tasking applications.
772 -- This function will always return Invalid_Pid under VxWorks, since there
773 -- is no notion of executables under this OS.
775 function Non_Blocking_Spawn
776 (Program_Name : String;
777 Args : Argument_List;
778 Output_File : String;
779 Err_To_Out : Boolean := True) return Process_Id;
780 -- Similar to the procedure above, but saves the output of the command to
781 -- a file with the name Output_File.
783 -- Success is set to True if the command is executed and its output
784 -- successfully written to the file. Invalid_Pid is returned if the output
785 -- file could not be created or if the program could not be spawned
788 -- "Non_Blocking_Spawn" should not be used in tasking applications.
790 -- This function will always return Invalid_Pid under VxWorks, since there
791 -- is no notion of executables under this OS.
793 procedure Wait_Process (Pid : out Process_Id; Success : out Boolean);
794 -- Wait for the completion of any of the processes created by previous
795 -- calls to Non_Blocking_Spawn. The caller will be suspended until one of
796 -- these processes terminates (normally or abnormally). If any of these
797 -- subprocesses terminates prior to the call to Wait_Process (and has not
798 -- been returned by a previous call to Wait_Process), then the call to
799 -- Wait_Process is immediate. Pid identifies the process that has
800 -- terminated (matching the value returned from Non_Blocking_Spawn).
801 -- Success is set to True if this sub-process terminated successfully. If
802 -- Pid = Invalid_Pid, there were no subprocesses left to wait on.
804 -- This function will always set success to False under VxWorks, since
805 -- there is no notion of executables under this OS.
807 function Argument_String_To_List
808 (Arg_String : String) return Argument_List_Access;
809 -- Take a string that is a program and its arguments and parse it into an
810 -- Argument_List. Note that the result is allocated on the heap, and must
811 -- be freed by the programmer (when it is no longer needed) to avoid
818 function Getenv (Name : String) return String_Access;
819 -- Get the value of the environment variable. Returns an access to the
820 -- empty string if the environment variable does not exist or has an
821 -- explicit null value (in some operating systems these are distinct
822 -- cases, in others they are not; this interface abstracts away that
823 -- difference. The argument is allocated on the heap (even in the null
824 -- case), and needs to be freed explicitly when no longer needed to avoid
827 procedure Setenv (Name : String; Value : String);
828 -- Set the value of the environment variable Name to Value. This call
829 -- modifies the current environment, but does not modify the parent
830 -- process environment. After a call to Setenv, Getenv (Name) will always
831 -- return a String_Access referencing the same String as Value. This is
832 -- true also for the null string case (the actual effect may be to either
833 -- set an explicit null as the value, or to remove the entry, this is
834 -- operating system dependent). Note that any following calls to Spawn
835 -- will pass an environment to the spawned process that includes the
836 -- changes made by Setenv calls. This procedure is not available on VMS.
838 procedure OS_Exit (Status : Integer);
839 pragma No_Return (OS_Exit);
841 -- Exit to OS with given status code (program is terminated). Note that
842 -- this is abrupt termination. All tasks are immediately terminated. There
843 -- are no finalization or other Ada-specific cleanup actions performed. On
844 -- systems with atexit handlers (such as Unix and Windows), atexit handlers
847 type OS_Exit_Subprogram is access procedure (Status : Integer);
849 procedure OS_Exit_Default (Status : Integer);
850 pragma No_Return (OS_Exit_Default);
851 -- Default implementation of procedure OS_Exit
853 OS_Exit_Ptr : OS_Exit_Subprogram := OS_Exit_Default'Access;
854 -- OS_Exit is implemented through this access value. It it then possible to
855 -- change the implementation of OS_Exit by redirecting OS_Exit_Ptr to an
856 -- other implementation.
859 pragma Import (C, OS_Abort, "abort");
860 pragma No_Return (OS_Abort);
861 -- Exit to OS signalling an abort (traceback or other appropriate
862 -- diagnostic information should be given if possible, or entry made to
863 -- the debugger if that is possible).
865 function Errno return Integer;
866 pragma Import (C, Errno, "__get_errno");
867 -- Return the task-safe last error number
869 procedure Set_Errno (Errno : Integer);
870 pragma Import (C, Set_Errno, "__set_errno");
871 -- Set the task-safe error number
873 Directory_Separator : constant Character;
874 -- The character that is used to separate parts of a pathname
876 Path_Separator : constant Character;
877 -- The character to separate paths in an environment variable value
880 pragma Import (C, Path_Separator, "__gnat_path_separator");
881 pragma Import (C, Directory_Separator, "__gnat_dir_separator");
882 pragma Import (C, Current_Time, "__gnat_current_time");
884 type OS_Time is new Long_Integer;
885 -- Type used for timestamps in the compiler. This type is used to hold
886 -- time stamps, but may have a different representation than C's time_t.
887 -- This type needs to match the declaration of OS_Time in adaint.h.
889 -- Add pragma Inline statements for comparison operations on OS_Time. It
890 -- would actually be nice to use pragma Import (Intrinsic) here, but this
891 -- was not properly supported till GNAT 3.15a, so that would cause
892 -- bootstrap path problems. To be changed later ???
894 Invalid_Time : constant OS_Time := -1;
895 -- This value should match the return value from __gnat_file_time_*
899 pragma Inline ("<=");
900 pragma Inline (">=");
902 type Process_Id is new Integer;
903 Invalid_Pid : constant Process_Id := -1;
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