ACE_Process Class Reference

Process. More...

#include <Process.h>

Inheritance diagram for ACE_Process:

[legend]Collaboration diagram for ACE_Process:

[legend]List of all members.

Public Member Functions
	ACE_Process (void)
	Default construction. Must use <ACE_Process::spawn> to start.
virtual	~ACE_Process (void)
	Destructor.
virtual int	prepare (ACE_Process_Options &options)
virtual pid_t	spawn (ACE_Process_Options &options)
virtual void	parent (pid_t child)
virtual void	child (pid_t parent)
virtual void	unmanage (void)
pid_t	wait (ACE_exitcode *status=0, int wait_options=0)
pid_t	wait (const ACE_Time_Value &tv, ACE_exitcode *status=0)
int	kill (int signum=SIGINT)
int	terminate (void)
pid_t	getpid (void) const
	Return the process id of the new child process.
ACE_HANDLE	gethandle (void) const
	Return the handle of the process, if it has one.
int	running (void) const
	Return 1 if running; 0 otherwise.
ACE_exitcode	exit_code (void) const
int	return_value (void) const
void	close_dup_handles (void)
void	close_passed_handles (void)
Protected Member Functions
void	exit_code (ACE_exitcode code)
Protected Attributes
pid_t	child_id_
	Process id of the child.
ACE_exitcode	exit_code_
ACE_Handle_Set	handles_passed_
	Set of handles that were passed to the child process.
ACE_Handle_Set	dup_handles_
	Handle duplicates made for the child process.
Private Member Functions
	ACE_Process (const ACE_Process &)
void	operator= (const ACE_Process &)
Friends
class	ACE_Process_Manager

---

Detailed Description

Process.

A Portable encapsulation for creating new processes. Notice that on UNIX platforms, if the <setenv> is used, the <spawn> is using the <execve> system call. It means that the <command_line> should include a full path to the program file (<execve> does not search the PATH). If <setenv> is not used then, the <spawn> is using the <execvp> which searches for the program file in the PATH variable.

Definition at line 447 of file Process.h.

---

Constructor & Destructor Documentation

ACE_BEGIN_VERSIONED_NAMESPACE_DECL ACE_Process::ACE_Process

(

void

)

Default construction. Must use <ACE_Process::spawn> to start.

Definition at line 45 of file Process.cpp.

References ACE_OS::memset().

  :
#if !defined (ACE_WIN32)
  child_id_ (ACE_INVALID_PID),
#endif /* !defined (ACE_WIN32) */
  exit_code_ (0)
{
#if defined (ACE_WIN32)
  ACE_OS::memset ((void *) &this->process_info_,
                  0,
                  sizeof this->process_info_);
#endif /* ACE_WIN32 */
}

ACE_Process::~ACE_Process

(

void

)

[virtual]

Destructor.

Definition at line 59 of file Process.cpp.

References ACE_OS::close(), and close_dup_handles().

{
#if defined (ACE_WIN32)
  // Free resources allocated in kernel.
  ACE_OS::close (this->process_info_.hThread);
  ACE_OS::close (this->process_info_.hProcess);
#endif /* ACE_WIN32 */
  // If any handles were duplicated for the child process and
  // still not closed, get them now.
  this->close_dup_handles ();
}

ACE_Process::ACE_Process

(

const ACE_Process &

)

[private]

---

Member Function Documentation

void ACE_Process::child

(

pid_t

parent

)

[virtual]

Called just after <ACE_OS::fork> in the child's context. The default does nothing. This function is *not* called on Win32 because the process-creation scheme does not allow it.

Definition at line 526 of file Process.cpp.

Referenced by spawn().

{
  // nothing to do
}

void ACE_Process::close_dup_handles

(

void

)

Close all the handles in the set obtained from the

• ACE_Process_Options::dup_handles object used to spawn the process.

Definition at line 686 of file Process.cpp.

References ACE_OS::closesocket(), dup_handles_, and ACE_Handle_Set::reset().

Referenced by ~ACE_Process().

{
  if (this->dup_handles_.num_set () > 0)
    {
      ACE_Handle_Set_Iterator h_iter (this->dup_handles_);
      for (ACE_HANDLE h = h_iter ();
           h != ACE_INVALID_HANDLE;
           h = h_iter ())
        ACE_OS::closesocket (h);
      this->dup_handles_.reset ();
    }
  return;
}

void ACE_Process::close_passed_handles

(

void

)

Close all the handles in the set obtained from the

• ACE_Process_Options::passed_handles object used to spawn the process.

Definition at line 701 of file Process.cpp.

References ACE_OS::closesocket(), handles_passed_, and ACE_Handle_Set::reset().

{
  if (this->handles_passed_.num_set () > 0)
    {
      ACE_Handle_Set_Iterator h_iter (this->handles_passed_);
      for (ACE_HANDLE h = h_iter ();
           h != ACE_INVALID_HANDLE;
           h = h_iter ())
        ACE_OS::closesocket (h);
      this->handles_passed_.reset ();
    }
  return;
}

ACE_INLINE void ACE_Process::exit_code

(

ACE_exitcode

code

)

[protected]

Set this process' <exit_code_>. ACE_Process_Manager uses this method to set the <exit_code_> after successfully waiting for this process to exit.

Definition at line 96 of file Process.inl.

References exit_code_.

{
  this->exit_code_ = code;
}

ACE_INLINE ACE_exitcode ACE_Process::exit_code

(

void

)

const

Return the Process' exit code. This method returns the raw exit status returned from system APIs (such as <wait> or <waitpid>). This value is system dependent.

Definition at line 90 of file Process.inl.

References exit_code_.

Referenced by ACE_Process_Manager::notify_proc_handler().

{
  return this->exit_code_;
}

ACE_BEGIN_VERSIONED_NAMESPACE_DECL ACE_INLINE ACE_HANDLE ACE_Process::gethandle

(

void

)

const

Return the handle of the process, if it has one.

Definition at line 23 of file Process.inl.

References child_id_.

Referenced by ACE_Process_Manager::append_proc(), and running().

{
#if defined (ACE_WIN32)
  return process_info_.hProcess;
#else
  return ACE_HANDLE (child_id_);
#endif /* ACE_WIN32 */
}

ACE_INLINE pid_t ACE_Process::getpid

(

void

)

const

Return the process id of the new child process.

Definition at line 33 of file Process.inl.

References child_id_.

Referenced by ACE_Process_Manager::handle_signal(), ACE_Process_Manager::insert_proc(), spawn(), ACE_Process_Manager::wait(), and wait().

{
#if defined (ACE_WIN32)
  return process_info_.dwProcessId;
#else /* ACE_WIN32 */
  return child_id_;
#endif /* ACE_WIN32 */
}

ACE_INLINE int ACE_Process::kill

(

int

signum = SIGINT

)

Send the process a signal. This is only portable to operating systems that support signals, such as UNIX/POSIX.

Definition at line 62 of file Process.inl.

References ACE_OS::kill().

{
  if (this->getpid () != -1)
    return ACE_OS::kill (this->getpid (), signum);
  else
    return -1;
}

void ACE_Process::operator=

(

const ACE_Process &

)

[private]

void ACE_Process::parent

(

pid_t

child

)

[virtual]

Called just after <ACE_OS::fork> in the parent's context, if the <fork> succeeds. The default is to do nothing.

Definition at line 520 of file Process.cpp.

Referenced by spawn().

{
  // nothing to do
}

int ACE_Process::prepare

(

ACE_Process_Options &

options

)

[virtual]

Called just before <ACE_OS::fork> in the <spawn>. If this returns non-zero, the <spawn> is aborted (and returns ACE_INVALID_PID). The default simply returns zero.

Definition at line 72 of file Process.cpp.

{
  return 0;
}

ACE_INLINE int ACE_Process::return_value

(

void

)

const

Return the Process' return value. This method returns the actual return value that a child process returns or <exit>s.

Definition at line 80 of file Process.inl.

References exit_code_, and WEXITSTATUS.

{
#if defined (ACE_WIN32)
  return this->exit_code_;
#else
  return WEXITSTATUS (this->exit_code_);
#endif /* ACE_WIN32 */
}

int ACE_Process::running

(

void

)

const

Return 1 if running; 0 otherwise.

Definition at line 538 of file Process.cpp.

References ACE_INVALID_PID, gethandle(), and ACE_OS::kill().

{
#if defined (ACE_WIN32)
    DWORD code;

    BOOL result = ::GetExitCodeProcess (this->gethandle (),
                                        &code);
    return result && code == STILL_ACTIVE;
#else
  if (ACE_INVALID_PID == this->getpid ())
    return 0;
  else
    return ACE_OS::kill (this->getpid (),
                         0) == 0
      || errno != ESRCH;
#endif /* ACE_WIN32 */
}

pid_t ACE_Process::spawn

(

ACE_Process_Options &

options

)

[virtual]

Launch a new process as described by options. On success, returns 1 if the option avoid_zombies is set, else returns the process id of the newly spawned child. Returns -1 on failure. This will be fixed in the future versions of ACE when the process id of the child will be returned regardless of the option.

Definition at line 78 of file Process.cpp.

References ACE_OS::_exit(), ACE_BIT_ENABLED, ACE_ERROR, ACE_INVALID_PID, ACE_NOTSUP_RETURN, ACE_STDERR, ACE_STDIN, ACE_STDOUT, ACE_TEXT, ACE_Process_Options::avoid_zombies(), ACE_OS::chdir(), child(), child_id_, ACE_OS::close(), ACE_Process_Options::command_line_argv(), ACE_Process_Options::command_line_buf(), ACE_Process_Options::creation_flags(), ACE_OS::dup(), ACE_OS::dup2(), ACE_Process_Options::dup_handles(), ACE_Process_Options::env_argv(), ACE_Process_Options::env_buf(), ACE_OS::execve(), ACE_OS::execvp(), ACE_OS::exit(), ACE::fork(), ACE_Process_Options::get_stderr(), ACE_Process_Options::get_stdin(), ACE_Process_Options::get_stdout(), ACE_Process_Options::getegid(), ACE_Process_Options::geteuid(), ACE_Process_Options::getgroup(), getpid(), ACE_OS::getppid(), ACE_Process_Options::getrgid(), ACE_Process_Options::getruid(), ACE_Process_Options::handle_inheritence(), ACE_Process_Options::inherit_environment(), LM_ERROR, ACE_Process_Options::NO_EXEC, parent(), ACE_Process_Options::passed_handles(), ACE_Process_Options::process_name(), ACE_OS::putenv(), ACE_OS::setpgid(), ACE_OS::setregid(), ACE_OS::setreuid(), ACE_OS::sprintf(), ACE_OS::strlen(), and ACE_Process_Options::working_directory().

Referenced by ACE_Process_Manager::spawn().

{
  if (this->prepare (options) < 0)
    return ACE_INVALID_PID;

  // Stash the passed/duped handle sets away in this object for later
  // closing if needed or requested. At the same time, figure out which
  // ones to include in command line options if that's needed below.
  ACE_Handle_Set *set_p = 0;
  if (options.dup_handles (this->dup_handles_))
    set_p = &this->dup_handles_;
  else if (options.passed_handles (this->handles_passed_))
    set_p = &this->handles_passed_;

  // If we are going to end up running a new program (i.e. Win32, or
  // NO_EXEC option is set) then get any handles passed in the options,
  // and tack them onto the command line with +H <handle> options,
  // unless the command line runs out of space.
  // Note that we're using the knowledge that all the options, argvs, etc.
  // passed to the options are all sitting in the command_line_buf. Any
  // call to get the argv then splits them out. So, regardless of the
  // platform, tack them all onto the command line buf and take it
  // from there.
  if (set_p && !ACE_BIT_ENABLED (options.creation_flags (),
                                 ACE_Process_Options::NO_EXEC))
    {
      int maxlen = 0;
      ACE_TCHAR *cmd_line_buf = options.command_line_buf (&maxlen);
      size_t max_len = static_cast<size_t> (maxlen);
      size_t curr_len = ACE_OS::strlen (cmd_line_buf);
      ACE_Handle_Set_Iterator h_iter (*set_p);
      // Because the length of the to-be-formatted +H option is not
      // known, and we don't have a snprintf, guess at the space
      // needed (20 chars), and use that as a limit.
      for (ACE_HANDLE h = h_iter ();
           h != ACE_INVALID_HANDLE && curr_len + 20 < max_len;
           h = h_iter ())
        {
#if defined (ACE_WIN32)
# if defined (ACE_WIN64)
          curr_len += ACE_OS::sprintf (&cmd_line_buf[curr_len],
                                       ACE_TEXT (" +H %I64p"),
                                       h);
# else
          curr_len += ACE_OS::sprintf (&cmd_line_buf[curr_len],
                                       ACE_TEXT (" +H %p"),
                                       h);
# endif  /* ACE_WIN64 */
#else
          curr_len += ACE_OS::sprintf (&cmd_line_buf[curr_len],
                                       ACE_TEXT (" +H %d"),
                                       h);
#endif /* ACE_WIN32 */
        }
    }

#if defined (ACE_HAS_WINCE)
  // Note that WinCE does not have process name included in the command line as argv[0]
  // like other OS environment.  Therefore, it is user's whole responsibility to call
  // 'ACE_Process_Options::process_name(const ACE_TCHAR *name)' to set the proper
  // process name (the execution file name with path if needed).

  BOOL fork_result =
    ACE_TEXT_CreateProcess (options.process_name(),
                            options.command_line_buf(),
                            options.get_process_attributes(),  // must be NULL in CE
                            options.get_thread_attributes(),   // must be NULL in CE
                            options.handle_inheritence(),      // must be false in CE
                            options.creation_flags(),          // must be NULL in CE
                            options.env_buf(),                 // environment variables, must be NULL in CE
                            options.working_directory(),       // must be NULL in CE
                            options.startup_info(),            // must be NULL in CE
                            &this->process_info_);

  if (fork_result)
    {
      parent (this->getpid ());
      return this->getpid ();
    }
  return ACE_INVALID_PID;

#elif defined (ACE_WIN32)
  BOOL fork_result =
    ACE_TEXT_CreateProcess (0,
                            options.command_line_buf (),
                            options.get_process_attributes (),
                            options.get_thread_attributes (),
                            options.handle_inheritence (),
                            options.creation_flags (),
                            options.env_buf (), // environment variables
                            options.working_directory (),
                            options.startup_info (),
                            &this->process_info_);

  if (fork_result)
    {
      parent (this->getpid ());
      return this->getpid ();
    }
  return ACE_INVALID_PID;

#elif defined(ACE_OPENVMS)
  if (ACE_BIT_ENABLED (options.creation_flags (),
                       ACE_Process_Options::NO_EXEC))
    ACE_NOTSUP_RETURN (ACE_INVALID_PID);

  int saved_stdin = ACE_STDIN;
  int saved_stdout = ACE_STDOUT;
  int saved_stderr = ACE_STDERR;
  // Save STD file descriptors and redirect
  if (options.get_stdin () != ACE_INVALID_HANDLE) {
    if ((saved_stdin = ACE_OS::dup (ACE_STDIN)) == -1 && errno != EBADF)
      ACE_OS::exit (errno);
    if (ACE_OS::dup2 (options.get_stdin (), ACE_STDIN) == -1)
      ACE_OS::exit (errno);
  }
  if (options.get_stdout () != ACE_INVALID_HANDLE) {
    if ((saved_stdout = ACE_OS::dup (ACE_STDOUT)) == -1 && errno != EBADF)
      ACE_OS::exit (errno);
    if (ACE_OS::dup2 (options.get_stdout (), ACE_STDOUT) == -1)
      ACE_OS::exit (errno);
  }
  if (options.get_stderr () != ACE_INVALID_HANDLE) {
    if ((saved_stderr = ACE_OS::dup (ACE_STDERR)) == -1 && errno != EBADF)
      ACE_OS::exit (errno);
    if (ACE_OS::dup2 (options.get_stderr (), ACE_STDERR) == -1)
      ACE_OS::exit (errno);
  }

  if (options.working_directory () != 0)
    ACE_NOTSUP_RETURN (ACE_INVALID_PID);

  this->child_id_ = vfork();
  if (this->child_id_ == 0) {
      ACE_OS::execvp (options.process_name (),
                options.command_line_argv ());
      // something went wrong
      this->child_id_ = ACE_INVALID_PID;
  }

  // restore STD file descriptors (if necessary)
  if (options.get_stdin () != ACE_INVALID_HANDLE) {
    if (saved_stdin == -1)
      ACE_OS::close (ACE_STDIN);
    else
      ACE_OS::dup2 (saved_stdin, ACE_STDIN);
  }
  if (options.get_stdout () != ACE_INVALID_HANDLE) {
    if (saved_stdout == -1)
      ACE_OS::close (ACE_STDOUT);
    else
      ACE_OS::dup2 (saved_stdout, ACE_STDOUT);
  }
  if (options.get_stderr () != ACE_INVALID_HANDLE) {
    if (saved_stderr == -1)
      ACE_OS::close (ACE_STDERR);
    else
      ACE_OS::dup2 (saved_stderr, ACE_STDERR);
  }

  return this->child_id_;
#elif (defined (ACE_VXWORKS) && (ACE_VXWORKS > 0x600)) && defined (__RTP__)
  if (ACE_BIT_ENABLED (options.creation_flags (),
                       ACE_Process_Options::NO_EXEC))
    ACE_NOTSUP_RETURN (ACE_INVALID_PID);

  if (options.working_directory () != 0)
    ACE_NOTSUP_RETURN (ACE_INVALID_PID);

  int saved_stdin = ACE_STDIN;
  int saved_stdout = ACE_STDOUT;
  int saved_stderr = ACE_STDERR;
  // Save STD file descriptors and redirect
  if (options.get_stdin () != ACE_INVALID_HANDLE) {
    if ((saved_stdin = ACE_OS::dup (ACE_STDIN)) == -1 && errno != EBADF)
      ACE_OS::exit (errno);
    if (ACE_OS::dup2 (options.get_stdin (), ACE_STDIN) == -1)
      ACE_OS::exit (errno);
  }
  if (options.get_stdout () != ACE_INVALID_HANDLE) {
    if ((saved_stdout = ACE_OS::dup (ACE_STDOUT)) == -1 && errno != EBADF)
      ACE_OS::exit (errno);
    if (ACE_OS::dup2 (options.get_stdout (), ACE_STDOUT) == -1)
      ACE_OS::exit (errno);
  }
  if (options.get_stderr () != ACE_INVALID_HANDLE) {
    if ((saved_stderr = ACE_OS::dup (ACE_STDERR)) == -1 && errno != EBADF)
      ACE_OS::exit (errno);
    if (ACE_OS::dup2 (options.get_stderr (), ACE_STDERR) == -1)
      ACE_OS::exit (errno);
  }

  // Wide-char builds need narrow-char strings for commandline and
  // environment variables.
# if defined (ACE_USES_WCHAR)
  wchar_t * const *wargv = options.command_line_argv ();
  size_t vcount, i;
  for (vcount = 0; wargv[vcount] != 0; ++vcount)
    ;
  char **procargv = new char *[vcount + 1];  // Need 0 at the end
  procargv[vcount] = 0;
  for (i = 0; i < vcount; ++i)
    procargv[i] = ACE_Wide_To_Ascii::convert (wargv[i]);

  char **procenv = 0;
  if (options.inherit_environment ())
    {
      wargv = options.env_argv ();
      for (vcount = 0; wargv[vcount] != 0; ++vcount)
        ;
      procenv = new char *[vcount + 1];  // Need 0 at the end
      procenv[vcount] = 0;
      for (i = 0; i < vcount; ++i)
        procenv[i] = ACE_Wide_To_Ascii::convert (wargv[i]);
    }
# else
  const char **procargv = const_cast<const char**> (options.command_line_argv ());
  const char **procenv = const_cast<const char**> (options.env_argv ());
# endif /* ACE_USES_WCHAR */

  this->child_id_ = ::rtpSpawn (procargv[0],
                                procargv,
                                procenv,
                                200,          // priority
                                0x10000,      // uStackSize
                                0,            // options
                                VX_FP_TASK);  // taskOptions
  int my_errno_ = errno;
  if (this->child_id_ == ERROR) {
      // something went wrong
      this->child_id_ = ACE_INVALID_PID;
  }

# if defined (ACE_USES_WCHAR)
  if (procenv)
    delete procenv;
# endif /* ACE_USES_WCHAR */

  // restore STD file descriptors (if necessary)
  if (options.get_stdin () != ACE_INVALID_HANDLE) {
    if (saved_stdin == -1)
      ACE_OS::close (ACE_STDIN);
    else
      ACE_OS::dup2 (saved_stdin, ACE_STDIN);
  }
  if (options.get_stdout () != ACE_INVALID_HANDLE) {
    if (saved_stdout == -1)
      ACE_OS::close (ACE_STDOUT);
    else
      ACE_OS::dup2 (saved_stdout, ACE_STDOUT);
  }
  if (options.get_stderr () != ACE_INVALID_HANDLE) {
    if (saved_stderr == -1)
      ACE_OS::close (ACE_STDERR);
    else
      ACE_OS::dup2 (saved_stderr, ACE_STDERR);
  }

  if (this->child_id_ == ACE_INVALID_PID)
    {
      errno = my_errno_;
    }

  return this->child_id_;
#else /* ACE_WIN32 */
  // Fork the new process.
  this->child_id_ = ACE::fork (options.process_name (),
                               options.avoid_zombies ());

  if (this->child_id_ == 0)
    {
# if !defined (ACE_LACKS_SETPGID)
      // If we're the child and the options specified a non-default
      // process group, try to set our pgid to it.  This allows the
      // <ACE_Process_Manager> to wait for processes by their
      // process-group.
      if (options.getgroup () != ACE_INVALID_PID
          && ACE_OS::setpgid (0,
                              options.getgroup ()) < 0)
        {
#if !defined (ACE_HAS_THREADS)
          // We can't emit this log message because ACE_ERROR(), etc.
          // will invoke async signal unsafe functions, which results
          // in undefined behavior in threaded programs.
          ACE_ERROR ((LM_ERROR,
                      ACE_TEXT ("%p.\n"),
                      ACE_TEXT ("ACE_Process::spawn: setpgid failed.")));
#endif
        }
# endif /* ACE_LACKS_SETPGID */

# if !defined (ACE_LACKS_SETREGID)
      if (options.getrgid () != (uid_t) -1
          || options.getegid () != (uid_t) -1)
        if (ACE_OS::setregid (options.getrgid (),
                              options.getegid ()) == -1)
          {
#if !defined (ACE_HAS_THREADS)
            // We can't emit this log message because ACE_ERROR(), etc.
            // will invoke async signal unsafe functions, which results
            // in undefined behavior in threaded programs.
            ACE_ERROR ((LM_ERROR,
                        ACE_TEXT ("%p.\n"),
                        ACE_TEXT ("ACE_Process::spawn: setregid failed.")));
#endif
          }
# endif /* ACE_LACKS_SETREGID */

# if !defined (ACE_LACKS_SETREUID)
      // Set user and group id's.
      if (options.getruid () != (uid_t) -1
          || options.geteuid () != (uid_t) -1)
        if (ACE_OS::setreuid (options.getruid (),
                              options.geteuid ()) == -1)
          {
#if !defined (ACE_HAS_THREADS)
            // We can't emit this log message because ACE_ERROR(), etc.
            // will invoke async signal unsafe functions, which results
            // in undefined behavior in threaded programs.
            ACE_ERROR ((LM_ERROR,
                        ACE_TEXT ("%p.\n"),
                        ACE_TEXT ("ACE_Process::spawn: setreuid failed.")));
#endif
          }
# endif /* ACE_LACKS_SETREUID */

      this->child (ACE_OS::getppid ());
    }
  else if (this->child_id_ != -1)
    this->parent (this->child_id_);

  // If we're not supposed to exec, return the process id.
  if (ACE_BIT_ENABLED (options.creation_flags (),
                       ACE_Process_Options::NO_EXEC))
    return this->child_id_;

  switch (this->child_id_)
    {
    case -1:
      // Error.
      return ACE_INVALID_PID;
    case 0:
      // Child process...exec the
      {
        if (options.get_stdin () != ACE_INVALID_HANDLE
            && ACE_OS::dup2 (options.get_stdin (),
                             ACE_STDIN) == -1)
          ACE_OS::exit (errno);
        else if (options.get_stdout () != ACE_INVALID_HANDLE
                 && ACE_OS::dup2 (options.get_stdout (),
                                  ACE_STDOUT) == -1)
          ACE_OS::exit (errno);
        else if (options.get_stderr () != ACE_INVALID_HANDLE
                 && ACE_OS::dup2 (options.get_stderr (),
                                  ACE_STDERR) == -1)
          ACE_OS::exit (errno);

        // close down unneeded descriptors
        ACE_OS::close (options.get_stdin ());
        ACE_OS::close (options.get_stdout ());
        ACE_OS::close (options.get_stderr ());

        // If we must, set the working directory for the child
        // process.
        if (options.working_directory () != 0)
          ACE_OS::chdir (options.working_directory ());
        // Should check for error here!

        // Child process executes the command.
        int result = 0;

        // Wide-char builds not on Windows need narrow-char strings for
        // exec() and environment variables. Don't need to worry about
        // releasing any of the converted string memory since this
        // process will either exec() or exit() shortly.
# if defined (ACE_USES_WCHAR)
        ACE_Wide_To_Ascii n_procname (options.process_name ());
        const char *procname = n_procname.char_rep ();

        wchar_t * const *wargv = options.command_line_argv ();
        size_t vcount, i;
        for (vcount = 0; wargv[vcount] != 0; ++vcount)
          ;
        char **procargv = new char *[vcount + 1];  // Need 0 at the end
        procargv[vcount] = 0;
        for (i = 0; i < vcount; ++i)
          procargv[i] = ACE_Wide_To_Ascii::convert (wargv[i]);

        wargv = options.env_argv ();
        for (vcount = 0; wargv[vcount] != 0; ++vcount)
          ;
        char **procenv = new char *[vcount + 1];  // Need 0 at the end
        procenv[vcount] = 0;
        for (i = 0; i < vcount; ++i)
          procenv[i] = ACE_Wide_To_Ascii::convert (wargv[i]);
# else
        const char *procname = options.process_name ();
        char *const *procargv = options.command_line_argv ();
        char *const *procenv = options.env_argv ();
# endif /* ACE_USES_WCHAR */

        if (options.inherit_environment ())
          {
            // Add the new environment variables to the environment
            // context of the context before doing an <execvp>.
            for (size_t i = 0; procenv[i] != 0; i++)
              if (ACE_OS::putenv (procenv[i]) != 0)
                return ACE_INVALID_PID;

            // Now the forked process has both inherited variables and
            // the user's supplied variables.
            result = ACE_OS::execvp (procname, procargv);
          }
        else
          {
# if defined (ghs)
            // GreenHills 1.8.8 (for VxWorks 5.3.x) can't compile this
            // code.  Processes aren't supported on VxWorks anyways.
            ACE_NOTSUP_RETURN (ACE_INVALID_PID);
# else
            result = ACE_OS::execve (procname, procargv, procenv);
# endif /* ghs */
          }
        if (result == -1)
          {
            // If the execv fails, this child needs to exit.

            // Exit with the errno so that the calling process can
            // catch this and figure out what went wrong.
            ACE_OS::_exit (errno);
          }
        // ... otherwise, this is never reached.
        return 0;
      }
    default:
      // Server process.  The fork succeeded.
      return this->child_id_;
    }
#endif /* ACE_WIN32 */
}

ACE_INLINE int ACE_Process::terminate

(

void

)

Terminate the process abruptly using <ACE::terminate_process>. This call doesn't give the process a chance to cleanup, so use it with caution...

Definition at line 71 of file Process.inl.

References ACE::terminate_process().

{
  if (this->getpid () != -1)
    return ACE::terminate_process (this->getpid ());
  else
    return -1;
}

void ACE_Process::unmanage

(

void

)

[virtual]

Called by a <Process_Manager> that is removing this Process from its table of managed Processes. Default is to do nothing.

Reimplemented in ACE_Managed_Process.

Definition at line 532 of file Process.cpp.

Referenced by ACE_Process_Manager::remove_proc().

{
  // nothing to do
}

pid_t ACE_Process::wait	(	const ACE_Time_Value &	tv,
		ACE_exitcode *	status = 0
	)

Timed wait for the process we've created to exit. A return value of -1 indicates that the something failed; 0 indicates that a timeout occurred. Otherwise, the child's process id is returned. If <status> != 0, it points to an integer where the function stores the child's exit status.

Note:

On UNIX platforms this function uses <ualarm>, i.e., it overwrites any existing alarm. In addition, it steals all <SIGCHLD>s during the timeout period, which will break another <ACE_Process_Manager> in the same process that's expecting <SIGCHLD> to kick off process reaping.

Definition at line 557 of file Process.cpp.

References ACE_INVALID_PID, exit_code_, getpid(), ACE_Time_Value::max_time, ACE_Time_Value::msec(), ACE_Sig_Action::register_action(), ACE_OS::set_errno_to_last_error(), SIGCHLD, sigchld_nop(), ACE_OS::sleep(), wait(), ACE_OS::waitpid(), WNOHANG, and ACE_Time_Value::zero.

{
#if defined (ACE_WIN32)
  // Don't try to get the process exit status if wait failed so we can
  // keep the original error code intact.
  switch (::WaitForSingleObject (process_info_.hProcess,
                                 tv.msec ()))
    {
    case WAIT_OBJECT_0:
        // The error status of <GetExitCodeProcess> is nonetheless not
        // tested because we don't know how to return the value.
        ::GetExitCodeProcess (process_info_.hProcess,
                              &this->exit_code_);
      if (status != 0)
        *status = this->exit_code_;
      return this->getpid ();
    case WAIT_TIMEOUT:
      errno = ETIME;
      return 0;
    default:
      ACE_OS::set_errno_to_last_error ();
      return -1;
    }
#elif defined(ACE_LACKS_UNIX_SIGNALS)
  if (tv == ACE_Time_Value::zero)
    {
      pid_t retv =
        ACE_OS::waitpid (this->child_id_,
                         &this->exit_code_,
                         WNOHANG);
      if (status != 0)
        *status = this->exit_code_;

      return retv;
    }

  if (tv == ACE_Time_Value::max_time)
# if defined (ACE_VXWORKS)
    {
      pid_t retv;
      while ( (retv = this->wait (status)) == ACE_INVALID_PID && errno == EINTR ) ;
      return retv;
    }
# else
     return this->wait (status);
# endif

  pid_t pid = 0;
  ACE_Time_Value sleeptm (1);    // 1 msec
  if (sleeptm > tv)              // if sleeptime > waittime
      sleeptm = tv;
  ACE_Time_Value tmo (tv);       // Need one we can change
  for (ACE_Countdown_Time time_left (&tmo); tmo > ACE_Time_Value::zero ; time_left.update ())
    {
      pid = ACE_OS::waitpid (this->getpid (),
                             &this->exit_code_,
                             WNOHANG);
      if (status != 0)
        *status = this->exit_code_;

      if (pid > 0 || pid == ACE_INVALID_PID)
        break;          // Got a child or an error - all done

      // pid 0, nothing is ready yet, so wait.
      // Do a (very) short sleep (only this thread sleeps).
      ACE_OS::sleep (sleeptm);
    }

  return pid;
#else /* !ACE_WIN32 && !ACE_LACKS_UNIX_SIGNALS */
  if (tv == ACE_Time_Value::zero)
    {
      pid_t retv =
        ACE_OS::waitpid (this->child_id_,
                         &this->exit_code_,
                         WNOHANG);
      if (status != 0)
        *status = this->exit_code_;

      return retv;
    }

  if (tv == ACE_Time_Value::max_time)
    return this->wait (status);

  // Need to wait but limited to specified time.
  // Force generation of SIGCHLD, even though we don't want to
  // catch it - just need it to interrupt the sleep below.
  // If this object has a reactor set, assume it was given at
  // open(), and there's already a SIGCHLD action set, so no
  // action is needed here.
  ACE_Sig_Action old_action;
  ACE_Sig_Action do_sigchld ((ACE_SignalHandler)sigchld_nop);
  do_sigchld.register_action (SIGCHLD, &old_action);

  pid_t pid;
  ACE_Time_Value tmo (tv);       // Need one we can change
  for (ACE_Countdown_Time time_left (&tmo); ; time_left.update ())
    {
      pid = ACE_OS::waitpid (this->getpid (),
                             &this->exit_code_,
                             WNOHANG);
      if (status != 0)
        *status = this->exit_code_;

      if (pid > 0 || pid == ACE_INVALID_PID)
        break;          // Got a child or an error - all done

      // pid 0, nothing is ready yet, so wait.
      // Do a sleep (only this thread sleeps) til something
      // happens. This relies on SIGCHLD interrupting the sleep.
      // If SIGCHLD isn't delivered, we'll need to do something
      // with sigaction to force it.
      if (-1 == ACE_OS::sleep (tmo) && errno == EINTR)
        continue;
      // Timed out
      pid = 0;
      break;
    }

  // Restore the previous SIGCHLD action if it was changed.
  old_action.register_action (SIGCHLD);

  return pid;
#endif /* ACE_WIN32 */
}

ACE_INLINE pid_t ACE_Process::wait	(	ACE_exitcode *	status = 0,
		int	wait_options = 0
	)

Wait for the process we've created to exit. If <status> != 0, it points to an integer where the function store the exit status of child process to. If <wait_options> == <WNOHANG> then return 0 and don't block if the child process hasn't exited yet. A return value of -1 represents the <wait> operation failed, otherwise, the child process id is returned.

Definition at line 44 of file Process.inl.

References exit_code_, and ACE_OS::wait().

Referenced by ACE_Process_Manager::wait(), and wait().

{
  pid_t retv =
    ACE_OS::wait (this->getpid (),
                  &this->exit_code_,
                  wait_options
#if defined (ACE_WIN32)
                  , process_info_.hProcess
#endif /* ACE_WIN32 */
                  );
  if (status != 0)
    *status = this->exit_code_;

  return retv;
}

---

Friends And Related Function Documentation

friend class ACE_Process_Manager [friend]

Definition at line 450 of file Process.h.

---

Member Data Documentation

pid_t ACE_Process::child_id_ [protected]

Process id of the child.

Definition at line 575 of file Process.h.

Referenced by gethandle(), getpid(), and spawn().

ACE_Handle_Set ACE_Process::dup_handles_ [protected]

Handle duplicates made for the child process.

Definition at line 582 of file Process.h.

Referenced by close_dup_handles().

ACE_exitcode ACE_Process::exit_code_ [protected]

Definition at line 577 of file Process.h.

Referenced by exit_code(), return_value(), and wait().

ACE_Handle_Set ACE_Process::handles_passed_ [protected]

Set of handles that were passed to the child process.

Definition at line 580 of file Process.h.

Referenced by close_passed_handles().

---

The documentation for this class was generated from the following files:

• Process.h
• Process.cpp
• Process.inl

---