| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT COMPILER COMPONENTS -- |
| -- -- |
| -- G N A T . O S _ L I B -- |
| -- -- |
| -- S p e c -- |
| -- -- |
| -- Copyright (C) 1995-2003 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- -- |
| -- 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. -- |
| -- -- |
| -- 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. -- |
| -- -- |
| -- GNAT was originally developed by the GNAT team at New York University. -- |
| -- Extensive contributions were provided by Ada Core Technologies Inc. -- |
| -- -- |
| ------------------------------------------------------------------------------ |
| |
| -- Operating system interface facilities |
| |
| -- 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"); |
| |
| 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. |
| |
| -- 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 ??? |
| |
| pragma Inline ("<"); |
| pragma Inline (">"); |
| pragma Inline ("<="); |
| pragma Inline (">="); |
| |
| type Process_Id is new Integer; |
| Invalid_Pid : constant Process_Id := -1; |
| |
| end GNAT.OS_Lib; |