-- --
-- S p e c --
-- --
--- Copyright (C) 1995-2003 Free Software Foundation, Inc. --
+-- Copyright (C) 1995-2009, Free Software Foundation, Inc. --
-- --
-- GNAT 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- --
+-- ware Foundation; either version 3, or (at your option) any later ver- --
-- sion. GNAT 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 GNAT; see file COPYING. If not, write --
--- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
--- MA 02111-1307, USA. --
+-- or FITNESS FOR A PARTICULAR PURPOSE. --
-- --
--- 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. --
+-- As a special exception under Section 7 of GPL version 3, you are granted --
+-- additional permissions described in the GCC Runtime Library Exception, --
+-- version 3.1, as published by the Free Software Foundation. --
+-- --
+-- You should have received a copy of the GNU General Public License and --
+-- a copy of the GCC Runtime Library Exception along with this program; --
+-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
+-- <http://www.gnu.org/licenses/>. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- This package contains types and procedures for interfacing to the
-- underlying OS. It is used by the GNAT compiler and by tools associated
-- with the GNAT compiler, and therefore works for the various operating
--- systems to which GNAT has been ported. This package will undoubtedly
--- grow as new services are needed by various tools.
-
--- This package tends to use fairly low-level Ada in order to not bring
--- in large portions of the RTL. For example, functions return access
--- to string as part of avoiding functions returning unconstrained types.
-
--- Except where specifically noted, these routines are portable across
--- all GNAT implementations on all supported operating systems.
-
-with System;
-with GNAT.Strings;
-
-package GNAT.OS_Lib is
-pragma Elaborate_Body (OS_Lib);
-
- subtype String_Access is Strings.String_Access;
- -- General purpose string access type. Some of the functions in this
- -- package allocate string results on the heap, and return a value of
- -- this type. Note that the caller is responsible for freeing this
- -- String to avoid memory leaks.
-
- function "=" (Left, Right : in String_Access) return Boolean
- renames Strings."=";
-
- procedure Free (X : in out String_Access) renames Strings.Free;
- -- This procedure is provided for freeing returned values of type
- -- String_Access
-
- subtype String_List is Strings.String_List;
- function "=" (Left, Right : in String_List) return Boolean
- renames Strings."=";
-
- function "&" (Left : String_Access; Right : String_Access)
- return String_List renames Strings."&";
- function "&" (Left : String_Access; Right : String_List)
- return String_List renames Strings."&";
- function "&" (Left : String_List; Right : String_Access)
- return String_List renames Strings."&";
- function "&" (Left : String_List; Right : String_List)
- return String_List renames Strings."&";
-
- subtype String_List_Access is Strings.String_List_Access;
- -- General purpose array and pointer for list of string accesses
- function "=" (Left, Right : in String_List_Access) return Boolean
- renames Strings."=";
-
- procedure Free (Arg : in out String_List_Access)
- renames Strings.Free;
- -- Frees the given array and all strings that its elements reference,
- -- and then sets the argument to null. Provided for freeing returned
- -- values of this type (including Argument_List_Access).
-
- ---------------------
- -- Time/Date Stuff --
- ---------------------
-
- -- The OS's notion of time is represented by the private type OS_Time.
- -- This is the type returned by the File_Time_Stamp functions to obtain
- -- the time stamp of a specified file. Functions and a procedure (modeled
- -- after the similar subprograms in package Calendar) are provided for
- -- extracting information from a value of this type. Although these are
- -- called GM, the intention is not that they provide GMT times in all
- -- cases but rather the actual (time-zone independent) time stamp of the
- -- file (of course in Unix systems, this *is* in GMT form).
-
- type OS_Time is private;
-
- subtype Year_Type is Integer range 1900 .. 2099;
- subtype Month_Type is Integer range 1 .. 12;
- subtype Day_Type is Integer range 1 .. 31;
- subtype Hour_Type is Integer range 0 .. 23;
- subtype Minute_Type is Integer range 0 .. 59;
- subtype Second_Type is Integer range 0 .. 59;
-
- function GM_Year (Date : OS_Time) return Year_Type;
- function GM_Month (Date : OS_Time) return Month_Type;
- function GM_Day (Date : OS_Time) return Day_Type;
- function GM_Hour (Date : OS_Time) return Hour_Type;
- function GM_Minute (Date : OS_Time) return Minute_Type;
- function GM_Second (Date : OS_Time) return Second_Type;
-
- function "<" (X, Y : OS_Time) return Boolean;
- function ">" (X, Y : OS_Time) return Boolean;
- function ">=" (X, Y : OS_Time) return Boolean;
- function "<=" (X, Y : OS_Time) return Boolean;
- -- Basic comparison operators on OS_Time with obvious meanings. Note
- -- that these have Intrinsic convention, so for example it is not
- -- permissible to create accesses to any of these functions.
-
- procedure GM_Split
- (Date : OS_Time;
- Year : out Year_Type;
- Month : out Month_Type;
- Day : out Day_Type;
- Hour : out Hour_Type;
- Minute : out Minute_Type;
- Second : out Second_Type);
-
- ----------------
- -- File Stuff --
- ----------------
-
- -- These routines give access to the open/creat/close/read/write level
- -- of I/O routines in the typical C library (these functions are not
- -- part of the ANSI C standard, but are typically available in all
- -- systems). See also package Interfaces.C_Streams for access to the
- -- stream level routines.
-
- -- Note on file names. If a file name is passed as type String in any
- -- of the following specifications, then the name is a normal Ada string
- -- and need not be NUL-terminated. However, a trailing NUL character is
- -- permitted, and will be ignored (more accurately, the NUL and any
- -- characters that follow it will be ignored).
-
- type File_Descriptor is new Integer;
- -- Corresponds to the int file handle values used in the C routines
-
- Standin : constant File_Descriptor := 0;
- Standout : constant File_Descriptor := 1;
- Standerr : constant File_Descriptor := 2;
- -- File descriptors for standard input output files
-
- Invalid_FD : constant File_Descriptor := -1;
- -- File descriptor returned when error in opening/creating file;
-
- type Mode is (Binary, Text);
- for Mode'Size use Integer'Size;
- for Mode use (Binary => 0, Text => 1);
- -- Used in all the Open and Create calls to specify if the file is to be
- -- opened in binary mode or text mode. In systems like Unix, this has no
- -- effect, but in systems capable of text mode translation, the use of
- -- Text as the mode parameter causes the system to do CR/LF translation
- -- and also to recognize the DOS end of file character on input. The use
- -- of Text where appropriate allows programs to take a portable Unix view
- -- of DOS-format files and process them appropriately.
-
- function Open_Read
- (Name : String;
- Fmode : Mode) return File_Descriptor;
- -- Open file Name for reading, returning file descriptor File descriptor
- -- returned is Invalid_FD if file cannot be opened.
-
- function Open_Read_Write
- (Name : String;
- Fmode : Mode) return File_Descriptor;
- -- Open file Name for both reading and writing, returning file
- -- descriptor. File descriptor returned is Invalid_FD if file cannot be
- -- opened.
-
- function Create_File
- (Name : String;
- Fmode : Mode) return File_Descriptor;
- -- Creates new file with given name for writing, returning file descriptor
- -- for subsequent use in Write calls. File descriptor returned is
- -- Invalid_FD if file cannot be successfully created
-
- function Create_New_File
- (Name : String;
- Fmode : Mode) return File_Descriptor;
- -- Create new file with given name for writing, returning file descriptor
- -- for subsequent use in Write calls. This differs from Create_File in
- -- that it fails if the file already exists. File descriptor returned is
- -- Invalid_FD if the file exists or cannot be created.
-
- Temp_File_Len : constant Integer := 12;
- -- Length of name returned by Create_Temp_File call (GNAT-XXXXXX & NUL)
-
- subtype Temp_File_Name is String (1 .. Temp_File_Len);
- -- String subtype set by Create_Temp_File
-
- procedure Create_Temp_File
- (FD : out File_Descriptor;
- Name : out Temp_File_Name);
- -- Create and open for writing a temporary file in the current working
- -- directory. The name of the file and the File Descriptor are returned.
- -- The File Descriptor returned is Invalid_FD in the case of failure.
- -- No mode parameter is provided. Since this is a temporary file,
- -- there is no point in doing text translation on it.
- -- On some OSes, the maximum number of temp files that can be
- -- created with this procedure may be limited. When the maximum is
- -- reached, this procedure returns Invalid_FD. On some OSes, there may be
- -- a race condition between processes trying to create temp files
- -- at the same time in the same directory using this procedure.
-
- procedure Create_Temp_File
- (FD : out File_Descriptor;
- Name : out String_Access);
- -- Create and open for writing a temporary file in the current working
- -- directory. The name of the file and the File Descriptor are returned.
- -- No mode parameter is provided. Since this is a temporary file,
- -- there is no point in doing text translation on it.
- -- It is the responsibility of the caller to deallocate the access value
- -- returned in Name.
- -- This procedure will always succeed if the current working directory
- -- is writable. If the current working directory is not writable, then
- -- Invalid_FD is returned for the file descriptor and null for the Name.
- -- There is no race condition problem between processes trying to
- -- create temp files at the same time in the same directory.
-
- procedure Close (FD : File_Descriptor; Status : out Boolean);
- -- Close file referenced by FD. Status is False if the underlying service
- -- failed. Reasons for failure include: disk full, disk quotas exceeded
- -- and invalid file descriptor (the file may have been closed twice).
-
- procedure Close (FD : File_Descriptor);
- -- Close file referenced by FD. This form is used when the caller
- -- wants to ignore any possible error (see above for error cases).
-
- procedure Delete_File (Name : String; Success : out Boolean);
- -- Deletes file. Success is set True or False indicating if the delete is
- -- successful.
-
- procedure Rename_File
- (Old_Name : String;
- New_Name : String;
- Success : out Boolean);
- -- Rename a file. Success is set True or False indicating if the
- -- rename is successful or not.
-
- -- The following defines the mode for the Copy_File procedure below.
- -- Note that "time stamps and other file attributes" in the descriptions
- -- below refers to the creation and last modification times, and also
- -- the file access (read/write/execute) status flags.
-
- type Copy_Mode is
- (Copy,
- -- Copy the file. It is an error if the target file already exists.
- -- The time stamps and other file attributes are preserved in the copy.
-
- Overwrite,
- -- If the target file exists, the file is replaced otherwise
- -- the file is just copied. The time stamps and other file
- -- attributes are preserved in the copy.
-
- Append);
- -- If the target file exists, the contents of the source file
- -- is appended at the end. Otherwise the source file is just
- -- copied. The time stamps and other file attributes are
- -- are preserved if the destination file does not exist.
-
- type Attribute is
- (Time_Stamps,
- -- Copy time stamps from source file to target file. All other
- -- attributes are set to normal default values for file creation.
-
- Full,
- -- All attributes are copied from the source file to the target
- -- file. This includes the timestamps, and for example also includes
- -- read/write/execute attributes in Unix systems.
-
- None);
- -- No attributes are copied. All attributes including the time stamp
- -- values are set to normal default values for file creation.
-
- -- Note: The default is Time_Stamps, which corresponds to the normal
- -- default on Windows style systems. Full corresponds to the typical
- -- effect of "cp -p" on Unix systems, and None corresponds to the
- -- typical effect of "cp" on Unix systems.
-
- -- Note: Time_Stamps and Full are not supported on VMS and VxWorks
-
- procedure Copy_File
- (Name : String;
- Pathname : String;
- Success : out Boolean;
- Mode : Copy_Mode := Copy;
- Preserve : Attribute := Time_Stamps);
- -- Copy a file. Name must designate a single file (no wild cards allowed).
- -- Pathname can be a filename or directory name. In the latter case Name
- -- is copied into the directory preserving the same file name. Mode
- -- defines the kind of copy, see above with the default being a normal
- -- copy in which the target file must not already exist. Success is set
- -- to True or False indicating if the copy is successful (depending on
- -- the specified Mode).
- --
- -- Note: this procedure is only supported to a very limited extent on
- -- VMS. The only supported mode is Overwrite, and the only supported
- -- value for Preserve is None, resulting in the default action which
- -- for Overwrite is to leave attributes unchanged. Furthermore, the
- -- copy only works for simple text files.
-
- procedure Copy_Time_Stamps (Source, Dest : String; Success : out Boolean);
- -- Copy Source file time stamps (last modification and last access time
- -- stamps) to Dest file. Source and Dest must be valid filenames,
- -- furthermore Dest must be writable. Success will be set to True if the
- -- operation was successful and False otherwise.
- --
- -- Note: this procedure is not supported on VMS and VxWorks. On these
- -- platforms, Success is always set to False.
-
- function Read
- (FD : File_Descriptor;
- A : System.Address;
- N : Integer) return Integer;
- -- Read N bytes to address A from file referenced by FD. Returned value
- -- is count of bytes actually read, which can be less than N at EOF.
-
- function Write
- (FD : File_Descriptor;
- A : System.Address;
- N : Integer) return Integer;
- -- Write N bytes from address A to file referenced by FD. The returned
- -- value is the number of bytes written, which can be less than N if
- -- a disk full condition was detected.
-
- Seek_Cur : constant := 1;
- Seek_End : constant := 2;
- Seek_Set : constant := 0;
- -- Used to indicate origin for Lseek call
-
- procedure Lseek
- (FD : File_Descriptor;
- offset : Long_Integer;
- origin : Integer);
- pragma Import (C, Lseek, "__gnat_lseek");
- -- Sets the current file pointer to the indicated offset value,
- -- relative to the current position (origin = SEEK_CUR), end of
- -- file (origin = SEEK_END), or start of file (origin = SEEK_SET).
-
- function File_Length (FD : File_Descriptor) return Long_Integer;
- pragma Import (C, File_Length, "__gnat_file_length");
- -- Get length of file from file descriptor FD
-
- function File_Time_Stamp (Name : String) return OS_Time;
- -- Given the name of a file or directory, Name, obtains and returns the
- -- time stamp. This function can be used for an unopened file.
-
- function File_Time_Stamp (FD : File_Descriptor) return OS_Time;
- -- Get time stamp of file from file descriptor FD
-
- function Normalize_Pathname
- (Name : String;
- Directory : String := "";
- Resolve_Links : Boolean := True;
- Case_Sensitive : Boolean := True) return String;
- -- Returns a file name as an absolute path name, resolving all relative
- -- directories, and symbolic links. The parameter Directory is a fully
- -- resolved path name for a directory, or the empty string (the default).
- -- Name is the name of a file, which is either relative to the given
- -- directory name, if Directory is non-null, or to the current working
- -- directory if Directory is null. The result returned is the normalized
- -- name of the file. For most cases, if two file names designate the same
- -- file through different paths, Normalize_Pathname will return the same
- -- canonical name in both cases. However, there are cases when this is
- -- not true; for example, this is not true in Unix for two hard links
- -- designating the same file.
- --
- -- If Resolve_Links is set to True, then the symbolic links, on systems
- -- that support them, will be fully converted to the name of the file
- -- or directory pointed to. This is slightly less efficient, since it
- -- requires system calls.
- --
- -- If Name cannot be resolved or is null on entry (for example if there is
- -- a circularity in symbolic links: A is a symbolic link for B, while B is
- -- a symbolic link for A), then Normalize_Pathname returns an empty string.
- --
- -- In VMS, if Name follows the VMS syntax file specification, it is first
- -- converted into Unix syntax. If the conversion fails, Normalize_Pathname
- -- returns an empty string.
- --
- -- For case-sensitive file systems, the value of Case_Sensitive parameter
- -- is ignored. In systems that have a non case-sensitive file system like
- -- Windows and OpenVMS, if this parameter is set OFF, then the result
- -- is returned folded to lower case, this allows to checks if two files
- -- are the same by applying this function to their names and by comparing
- -- the results of these calls. If Case_Sensitive is ON, this function does
- -- not change the casing of file and directory names.
-
- function Is_Absolute_Path (Name : String) return Boolean;
- -- Returns True if Name is an absolute path name, i.e. it designates
- -- a file or a directory absolutely, rather than relative to another
- -- directory.
-
- function Is_Regular_File (Name : String) return Boolean;
- -- Determines if the given string, Name, is the name of an existing
- -- regular file. Returns True if so, False otherwise. Name may be an
- -- absolute path name or a relative path name, including a simple file
- -- name. If it is a relative path name, it is relative to the current
- -- working directory.
-
- function Is_Directory (Name : String) return Boolean;
- -- Determines if the given string, Name, is the name of a directory.
- -- Returns True if so, False otherwise. Name may be an absolute path
- -- name or a relative path name, including a simple file name. If it is
- -- a relative path name, it is relative to the current working directory.
-
- function Is_Readable_File (Name : String) return Boolean;
- -- Determines if the given string, Name, is the name of an existing
- -- file that is readable. Returns True if so, False otherwise. Note
- -- that this function simply interrogates the file attributes (e.g.
- -- using the C function stat), so it does not indicate a situation
- -- in which a file may not actually be readable due to some other
- -- process having exclusive access.
-
- function Is_Writable_File (Name : String) return Boolean;
- -- Determines if the given string, Name, is the name of an existing
- -- file that is writable. Returns True if so, False otherwise. Note
- -- that this function simply interrogates the file attributes (e.g.
- -- using the C function stat), so it does not indicate a situation
- -- in which a file may not actually be writeable due to some other
- -- process having exclusive access.
-
- function Is_Symbolic_Link (Name : String) return Boolean;
- -- Determines if the given string, Name, is the path of a symbolic link
- -- on systems that support it. Returns True if so, False if the path
- -- is not a symbolic link or if the system does not support symbolic links.
- --
- -- A symbolic link is an indirect pointer to a file; its directory entry
- -- contains the name of the file to which it is linked. Symbolic links may
- -- span file systems and may refer to directories.
-
- function Locate_Exec_On_Path
- (Exec_Name : String) return String_Access;
- -- Try to locate an executable whose name is given by Exec_Name in the
- -- directories listed in the environment Path. If the Exec_Name doesn't
- -- have the executable suffix, it will be appended before the search.
- -- Otherwise works like Locate_Regular_File below.
- --
- -- Note that this function allocates some memory for the returned value.
- -- This memory needs to be deallocated after use.
-
- function Locate_Regular_File
- (File_Name : String;
- Path : String) return String_Access;
- -- Try to locate a regular file whose name is given by File_Name in the
- -- directories listed in Path. If a file is found, its full pathname is
- -- returned; otherwise, a null pointer is returned. If the File_Name given
- -- is an absolute pathname, then Locate_Regular_File just checks that the
- -- file exists and is a regular file. Otherwise, if the File_Name given
- -- includes directory information, Locate_Regular_File first checks if
- -- the file exists relative to the current directory. If it does not,
- -- or if the File_Name given is a simple file name, the Path argument is
- -- parsed according to OS conventions, and for each directory in the Path
- -- a check is made if File_Name is a relative pathname of a regular file
- -- from that directory.
- --
- -- Note that this function allocates some memory for the returned value.
- -- This memory needs to be deallocated after use.
-
- function Get_Debuggable_Suffix return String_Access;
- -- Return the debuggable suffix convention. Usually this is the same as
- -- the convention for Get_Executable_Suffix. The result is allocated on
- -- the heap and should be freed when no longer needed to avoid storage
- -- leaks.
-
- function Get_Executable_Suffix return String_Access;
- -- Return the executable suffix convention. The result is allocated on
- -- the heap and should be freed when no longer needed to avoid storage
- -- leaks.
-
- function Get_Object_Suffix return String_Access;
- -- Return the object suffix convention. The result is allocated on the
- -- heap and should be freed when no longer needed to avoid storage leaks.
-
- -- The following section contains low-level routines using addresses to
- -- pass file name and executable name. In each routine the name must be
- -- Nul-Terminated. For complete documentation refer to the equivalent
- -- routine (using String in place of C_File_Name) defined above.
-
- subtype C_File_Name is System.Address;
- -- This subtype is used to document that a parameter is the address
- -- of a null-terminated string containing the name of a file.
-
- -- All the following functions need comments ???
-
- function Open_Read
- (Name : C_File_Name;
- Fmode : Mode) return File_Descriptor;
-
- function Open_Read_Write
- (Name : C_File_Name;
- Fmode : Mode) return File_Descriptor;
-
- function Create_File
- (Name : C_File_Name;
- Fmode : Mode) return File_Descriptor;
-
- function Create_New_File
- (Name : C_File_Name;
- Fmode : Mode) return File_Descriptor;
-
- procedure Delete_File (Name : C_File_Name; Success : out Boolean);
-
- procedure Rename_File
- (Old_Name : C_File_Name;
- New_Name : C_File_Name;
- Success : out Boolean);
-
- procedure Copy_File
- (Name : C_File_Name;
- Pathname : C_File_Name;
- Success : out Boolean;
- Mode : Copy_Mode := Copy;
- Preserve : Attribute := Time_Stamps);
-
- procedure Copy_Time_Stamps
- (Source, Dest : C_File_Name;
- Success : out Boolean);
-
- function File_Time_Stamp (Name : C_File_Name) return OS_Time;
-
- function Is_Regular_File (Name : C_File_Name) return Boolean;
-
- function Is_Directory (Name : C_File_Name) return Boolean;
-
- function Is_Readable_File (Name : C_File_Name) return Boolean;
- function Is_Writable_File (Name : C_File_Name) return Boolean;
- function Is_Symbolic_Link (Name : C_File_Name) return Boolean;
-
- function Locate_Regular_File
- (File_Name : C_File_Name;
- Path : C_File_Name)
- return String_Access;
-
- ------------------
- -- Subprocesses --
- ------------------
-
- subtype Argument_List is String_List;
- -- Type used for argument list in call to Spawn. The lower bound
- -- of the array should be 1, and the length of the array indicates
- -- the number of arguments.
-
- subtype Argument_List_Access is String_List_Access;
- -- Type used to return Argument_List without dragging in secondary stack.
- -- Note that there is a Free procedure declared for this subtype which
- -- frees the array and all referenced strings.
-
- procedure Normalize_Arguments (Args : in out Argument_List);
- -- Normalize all arguments in the list. This ensure that the argument list
- -- is compatible with the running OS and will works fine with Spawn and
- -- Non_Blocking_Spawn for example. If Normalize_Arguments is called twice
- -- on the same list it will do nothing the second time. Note that Spawn
- -- and Non_Blocking_Spawn call Normalize_Arguments automatically, but
- -- since there is a guarantee that a second call does nothing, this
- -- internal call will have no effect if Normalize_Arguments is called
- -- before calling Spawn. The call to Normalize_Arguments assumes that
- -- the individual referenced arguments in Argument_List are on the heap,
- -- and may free them and reallocate if they are modified.
-
- procedure Spawn
- (Program_Name : String;
- Args : Argument_List;
- Success : out Boolean);
- -- The first parameter of function Spawn is the name of the executable.
- -- The second parameter contains the arguments to be passed to the
- -- program. Success is False if the named program could not be spawned
- -- or its execution completed unsuccessfully. Note that the caller will
- -- be blocked until the execution of the spawned program is complete.
- -- For maximum portability, use a full path name for the Program_Name
- -- argument. On some systems (notably Unix systems) a simple file
- -- name may also work (if the executable can be located in the path).
- --
- -- "Spawn" should not be used in tasking applications.
- --
- -- Note: Arguments in Args that contain spaces and/or quotes such as
- -- "--GCC=gcc -v" or "--GCC=""gcc -v""" are not portable across all
- -- operating systems, and would not have the desired effect if they
- -- were passed directly to the operating system. To avoid this problem,
- -- Spawn makes an internal call to Normalize_Arguments, which ensures
- -- that such arguments are modified in a manner that ensures that the
- -- desired effect is obtained on all operating systems. The caller may
- -- call Normalize_Arguments explicitly before the call (e.g. to print
- -- out the exact form of arguments passed to the operating system). In
- -- this case the guarantee a second call to Normalize_Arguments has no
- -- effect ensures that the internal call will not affect the result.
- -- Note that the implicit call to Normalize_Arguments may free and
- -- reallocate some of the individual arguments.
- --
- -- This function will always set Success to False under VxWorks and
- -- other similar operating systems which have no notion of the concept
- -- of a dynamically executable file.
-
- function Spawn
- (Program_Name : String;
- Args : Argument_List)
- return Integer;
- -- Similar to the above procedure, but returns the actual status returned
- -- by the operating system, or -1 under VxWorks and any other similar
- -- operating systems which have no notion of separately spawnable programs.
- --
- -- "Spawn" should not be used in tasking applications.
- --
-
- type Process_Id is private;
- -- A private type used to identify a process activated by the following
- -- non-blocking call. The only meaningful operation on this type is a
- -- comparison for equality.
-
- Invalid_Pid : constant Process_Id;
- -- A special value used to indicate errors, as described below.
-
- function Non_Blocking_Spawn
- (Program_Name : String;
- Args : Argument_List)
- return Process_Id;
- -- This is a non blocking call. The Process_Id of the spawned process
- -- is returned. Parameters are to be used as in Spawn. If Invalid_Id
- -- is returned the program could not be spawned.
- --
- -- "Non_Blocking_Spawn" should not be used in tasking applications.
- --
- -- This function will always return Invalid_Id under VxWorks, since
- -- there is no notion of executables under this OS.
-
- procedure Wait_Process (Pid : out Process_Id; Success : out Boolean);
- -- Wait for the completion of any of the processes created by previous
- -- calls to Non_Blocking_Spawn. The caller will be suspended until one
- -- of these processes terminates (normally or abnormally). If any of
- -- these subprocesses terminates prior to the call to Wait_Process (and
- -- has not been returned by a previous call to Wait_Process), then the
- -- call to Wait_Process is immediate. Pid identifies the process that
- -- has terminated (matching the value returned from Non_Blocking_Spawn).
- -- Success is set to True if this sub-process terminated successfully.
- -- If Pid = Invalid_Id, there were no subprocesses left to wait on.
- --
- -- This function will always set success to False under VxWorks, since
- -- there is no notion of executables under this OS.
-
- function Argument_String_To_List
- (Arg_String : String)
- return Argument_List_Access;
- -- Take a string that is a program and its arguments and parse it into
- -- an Argument_List. Note that the result is allocated on the heap, and
- -- must be freed by the programmer (when it is no longer needed) to avoid
- -- memory leaks.
-
- -------------------
- -- Miscellaneous --
- -------------------
-
- function Getenv (Name : String) return String_Access;
- -- Get the value of the environment variable. Returns an access
- -- to the empty string if the environment variable does not exist
- -- or has an explicit null value (in some operating systems these
- -- are distinct cases, in others they are not; this interface
- -- abstracts away that difference. The argument is allocated on
- -- the heap (even in the null case), and needs to be freed explicitly
- -- when no longer needed to avoid memory leaks.
-
- procedure Setenv (Name : String; Value : String);
- -- Set the value of the environment variable Name to Value. This call
- -- modifies the current environment, but does not modify the parent
- -- process environment. After a call to Setenv, Getenv (Name) will
- -- always return a String_Access referencing the same String as Value.
- -- This is true also for the null string case (the actual effect may
- -- be to either set an explicit null as the value, or to remove the
- -- entry, this is operating system dependent). Note that any following
- -- calls to Spawn will pass an environment to the spawned process that
- -- includes the changes made by Setenv calls. This procedure is not
- -- available under VMS.
-
- procedure OS_Exit (Status : Integer);
- pragma Import (C, OS_Exit, "__gnat_os_exit");
- pragma No_Return (OS_Exit);
- -- Exit to OS with given status code (program is terminated)
-
- procedure OS_Abort;
- pragma Import (C, OS_Abort, "abort");
- pragma No_Return (OS_Abort);
- -- Exit to OS signalling an abort (traceback or other appropriate
- -- diagnostic information should be given if possible, or entry made
- -- to the debugger if that is possible).
-
- function Errno return Integer;
- pragma Import (C, Errno, "__get_errno");
- -- Return the task-safe last error number.
-
- procedure Set_Errno (Errno : Integer);
- pragma Import (C, Set_Errno, "__set_errno");
- -- Set the task-safe error number.
-
- Directory_Separator : constant Character;
- -- The character that is used to separate parts of a pathname.
-
- Path_Separator : constant Character;
- -- The character to separate paths in an environment variable value.
-
-private
- pragma Import (C, Path_Separator, "__gnat_path_separator");
- pragma Import (C, Directory_Separator, "__gnat_dir_separator");
+-- systems to which GNAT has been ported. This package will undoubtedly grow
+-- as new services are needed by various tools.
- type OS_Time is new Long_Integer;
- -- Type used for timestamps in the compiler. This type is used to
- -- hold time stamps, but may have a different representation than
- -- C's time_t. This type needs to match the declaration of OS_Time
- -- in adaint.h.
+-- This package tends to use fairly low-level Ada in order to not bring in
+-- large portions of the RTL. For example, functions return access to string
+-- as part of avoiding functions returning unconstrained types.
- -- Add pragma Inline statements for comparison operations on OS_Time.
- -- It would actually be nice to use pragma Import (Intrinsic) here,
- -- but this was not properly supported till GNAT 3.15a, so that would
- -- cause bootstrap path problems. To be changed later ???
+-- Except where specifically noted, these routines are portable across all
+-- GNAT implementations on all supported operating systems.
- pragma Inline ("<");
- pragma Inline (">");
- pragma Inline ("<=");
- pragma Inline (">=");
+-- See file s-os_lib.ads for full documentation of the interface
- type Process_Id is new Integer;
- Invalid_Pid : constant Process_Id := -1;
+with System.OS_Lib;
-end GNAT.OS_Lib;
+package GNAT.OS_Lib renames System.OS_Lib;
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