/*

Copyright (C) 1996, 1997, 1998, 1999, 2000, 2002, 2003, 2004, 2005,
              2006, 2007, 2008, 2009 John W. Eaton
Copyright (C) 2010 VZLU Prague

This file is part of Octave.

Octave is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 3 of the License, or (at your
option) any later version.

Octave is distributed in the hope that it will be useful, but WITHOUT
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
along with Octave; see the file COPYING.  If not, see
<http://www.gnu.org/licenses/>.

*/

// Thomas Baier <baier@ci.tuwien.ac.at> added the original versions of
// the following functions:
//
//   mkfifo  unlink  waitpid

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <cstdio>
#include <cstring>

#include <sys/types.h>
#include <unistd.h>

#include <fcntl.h>

#include "file-ops.h"
#include "file-stat.h"
#include "oct-syscalls.h"
#include "oct-uname.h"

#include "defun.h"
#include "error.h"
#include "gripes.h"
#include "lo-utils.h"
#include "oct-map.h"
#include "oct-obj.h"
#include "oct-stdstrm.h"
#include "oct-stream.h"
#include "sysdep.h"
#include "utils.h"
#include "variables.h"
#include "input.h"

static octave_scalar_map
mk_stat_map (const base_file_stat& fs)
{
  octave_scalar_map m;

  m.assign ("dev", static_cast<double> (fs.dev ()));
  m.assign ("ino", fs.ino ());
  m.assign ("mode", fs.mode ());
  m.assign ("modestr", fs.mode_as_string ());
  m.assign ("nlink", fs.nlink ());
  m.assign ("uid", fs.uid ());
  m.assign ("gid", fs.gid ());
#if defined (HAVE_STRUCT_STAT_ST_RDEV)
  m.assign ("rdev", static_cast<double> (fs.rdev ()));
#endif
  m.assign ("size", fs.size ());
  m.assign ("atime", fs.atime ());
  m.assign ("mtime", fs.mtime ());
  m.assign ("ctime", fs.ctime ());
#if defined (HAVE_STRUCT_STAT_ST_BLKSIZE)
  m.assign ("blksize", fs.blksize ());
#endif
#if defined (HAVE_STRUCT_STAT_ST_BLOCKS)
  m.assign ("blocks", fs.blocks ());
#endif

  return m;
}

static octave_value_list
mk_stat_result (const base_file_stat& fs)
{
  octave_value_list retval;

  if (fs)
    {
      retval(2) = std::string ();
      retval(1) = 0;
      retval(0) = octave_value (mk_stat_map (fs));
    }
  else
    {
      retval(2) = fs.error ();
      retval(1) = -1;
      retval(0) = Matrix ();
    }

  return retval;
}

DEFUNX ("dup2", Fdup2, args, ,
 "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {[@var{fid}, @var{msg}] =} dup2 (@var{old}, @var{new})\n\
Duplicate a file descriptor.\n\
\n\
If successful, @var{fid} is greater than zero and contains the new file\n\
ID.  Otherwise, @var{fid} is negative and @var{msg} contains a\n\
system-dependent error message.\n\
@end deftypefn")
{
  octave_value_list retval;

  retval(1) = std::string ();
  retval(0) = -1;

  int nargin = args.length ();

  if (nargin == 2)
    {
      octave_stream old_stream
        = octave_stream_list::lookup (args(0), "dup2");

      if (! error_state)
        {
          octave_stream new_stream
            = octave_stream_list::lookup (args(1), "dup2");

          if (! error_state)
            {
              int i_old = old_stream.file_number ();
              int i_new = new_stream.file_number ();

              if (i_old >= 0 && i_new >= 0)
                {
                  std::string msg;

                  int status = octave_syscalls::dup2 (i_old, i_new, msg);

                  retval(0) = status;
                  retval(1) = msg;
                }
            }
        }
      else
        error ("dup2: invalid stream");
    }
  else
    print_usage ();

  return retval;
}

DEFUNX ("exec", Fexec, args, ,
 "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {[@var{err}, @var{msg}] =} exec (@var{file}, @var{args})\n\
Replace current process with a new process.  Calling @code{exec} without\n\
first calling @code{fork} will terminate your current Octave process and\n\
replace it with the program named by @var{file}.  For example,\n\
\n\
@example\n\
exec (\"ls\" \"-l\")\n\
@end example\n\
\n\
@noindent\n\
will run @code{ls} and return you to your shell prompt.\n\
\n\
If successful, @code{exec} does not return.  If @code{exec} does return,\n\
@var{err} will be nonzero, and @var{msg} will contain a system-dependent\n\
error message.\n\
@end deftypefn")
{
  octave_value_list retval;

  retval(1) = std::string ();
  retval(0) = -1;

  int nargin = args.length ();

  if (nargin == 1 || nargin == 2)
    {
      std::string exec_file = args(0).string_value ();

      if (! error_state)
        {
          string_vector exec_args;

          if (nargin == 2)
            {
              string_vector tmp = args(1).all_strings ();

              if (! error_state)
                {
                  int len = tmp.length ();

                  exec_args.resize (len + 1);

                  exec_args[0] = exec_file;

                  for (int i = 0; i < len; i++)
                    exec_args[i+1] = tmp[i];
                }
              else
                error ("exec: arguments must be character strings");
            }
          else
            {
              exec_args.resize (1);

              exec_args[0] = exec_file;
            }

          if (! error_state)
            {
              std::string msg;

              int status = octave_syscalls::execvp (exec_file, exec_args, msg);

              retval(0) = status;
              retval(1) = msg;
            }
        }
      else
        error ("exec: first argument must be a string");
    }
  else
    print_usage ();

  return retval;
}

DEFUNX ("popen2", Fpopen2, args, ,
 "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {[@var{in}, @var{out}, @var{pid}] =} popen2 (@var{command}, @var{args})\n\
Start a subprocess with two-way communication.  The name of the process\n\
is given by @var{command}, and @var{args} is an array of strings\n\
containing options for the command.  The file identifiers for the input\n\
and output streams of the subprocess are returned in @var{in} and\n\
@var{out}.  If execution of the command is successful, @var{pid}\n\
contains the process ID of the subprocess.  Otherwise, @var{pid} is\n\
@minus{}1.\n\
\n\
For example,\n\
\n\
@example\n\
[in, out, pid] = popen2 (\"sort\", \"-r\");\n\
fputs (in, \"these\\nare\\nsome\\nstrings\\n\");\n\
fclose (in);\n\
EAGAIN = errno (\"EAGAIN\");\n\
done = false;\n\
do\n\
  s = fgets (out);\n\
  if (ischar (s))\n\
    fputs (stdout, s);\n\
  elseif (errno () == EAGAIN)\n\
    sleep (0.1);\n\
    fclear (out);\n\
  else\n\
    done = true;\n\
  endif\n\
until (done)\n\
fclose (out);\n\
waitpid (pid);\n\
     @print{} these\n\
     @print{} strings\n\
     @print{} some\n\
     @print{} are\n\
@end example\n\
\n\
Note that @code{popen2}, unlike @code{popen}, will not \"reap\" the\n\
child process.  If you don't use @code{waitpid} to check the child's\n\
exit status, it will linger until Octave exits.\n\
@end deftypefn")
{
  octave_value_list retval;

  retval(2) = -1;
  retval(1) = Matrix ();
  retval(0) = Matrix ();

  int nargin = args.length ();

  if (nargin >= 1 && nargin <= 3)
    {
      std::string exec_file = args(0).string_value();

      if (! error_state)
        {
          string_vector arg_list;

          if (nargin >= 2)
            {
              string_vector tmp = args(1).all_strings ();

              if (! error_state)
                {
                  int len = tmp.length ();

                  arg_list.resize (len + 1);

                  arg_list[0] = exec_file;

                  for (int i = 0; i < len; i++)
                    arg_list[i+1] = tmp[i];
                }
              else
                error ("popen2: arguments must be character strings");
            }
          else
            {
              arg_list.resize (1);

              arg_list[0] = exec_file;
            }

          if (! error_state)
            {
              bool sync_mode = (nargin == 3 ? args(2).bool_value() : false);

              if (! error_state)
                {
                  int fildes[2];
                  std::string msg;
                  pid_t pid;

                  pid = octave_syscalls::popen2 (exec_file, arg_list, sync_mode, fildes, msg, interactive);
                  if (pid >= 0)
                    {
                      FILE *ifile = fdopen (fildes[1], "r");
                      FILE *ofile = fdopen (fildes[0], "w");

                      std::string nm;

                      octave_stream is = octave_stdiostream::create (nm, ifile,
                          std::ios::in);

                      octave_stream os = octave_stdiostream::create (nm, ofile,
                          std::ios::out);

                      Cell file_ids (1, 2);

                      retval(0) = octave_stream_list::insert (os);
                      retval(1) = octave_stream_list::insert (is);
                                          retval(2) = pid;
                    }
                                  else
                    error (msg.c_str ());
                }
            }
          else
            error ("popen2: arguments must be character strings");
        }
      else
        error ("popen2: first argument must be a string");
    }
  else
    print_usage ();

  return retval;
}

/*

%!test
%!  if (isunix())
%!    [in, out, pid] = popen2 ("sort", "-r");
%!    EAGAIN = errno ("EAGAIN");
%!  else
%!    [in, out, pid] = popen2 ("sort", "/R");
%!    EAGAIN = errno ("EINVAL");
%!  endif
%!  fputs (in, "these\nare\nsome\nstrings\n");
%!  fclose (in);
%!  done = false;
%!  str = {};
%!  idx = 0;
%!  errs = 0;
%!  do
%!     if (!isunix())
%!       errno (0);
%!     endif
%!     s = fgets (out);
%!     if (ischar (s))
%!       idx++;
%!       str{idx} = s;
%!     elseif (errno () == EAGAIN)
%!       fclear (out);
%!       sleep (0.1);
%!       if (++errs == 100)
%!         done = true;
%!       endif
%!     else
%!       done = true;
%!     endif
%!  until (done)
%!  fclose (out);
%!  if (isunix())
%!    assert(str,{"these\n","strings\n","some\n","are\n"})
%!  else
%!    assert(str,{"these\r\n","strings\r\n","some\r\n","are\r\n"})
%!  end

*/

DEFUNX ("fcntl", Ffcntl, args, ,
 "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {[@var{err}, @var{msg}] =} fcntl (@var{fid}, @var{request}, @var{arg})\n\
Change the properties of the open file @var{fid}.  The following values\n\
may be passed as @var{request}:\n\
\n\
@vtable @code\n\
@item F_DUPFD\n\
Return a duplicate file descriptor.\n\
\n\
@item F_GETFD\n\
Return the file descriptor flags for @var{fid}.\n\
\n\
@item F_SETFD\n\
Set the file descriptor flags for @var{fid}.\n\
\n\
@item F_GETFL\n\
Return the file status flags for @var{fid}.  The following codes may be\n\
returned (some of the flags may be undefined on some systems).\n\
\n\
@vtable @code\n\
@item O_RDONLY\n\
Open for reading only.\n\
\n\
@item O_WRONLY\n\
Open for writing only.\n\
\n\
@item O_RDWR\n\
Open for reading and writing.\n\
\n\
@item O_APPEND\n\
Append on each write.\n\
\n\
@item O_CREAT\n\
Create the file if it does not exist.\n\
\n\
@item O_NONBLOCK\n\
Nonblocking mode.\n\
\n\
@item O_SYNC\n\
Wait for writes to complete.\n\
\n\
@item O_ASYNC\n\
Asynchronous I/O.\n\
@end vtable\n\
\n\
@item F_SETFL\n\
Set the file status flags for @var{fid} to the value specified by\n\
@var{arg}.  The only flags that can be changed are @w{@code{O_APPEND}} and\n\
@w{@code{O_NONBLOCK}}.\n\
@end vtable\n\
\n\
If successful, @var{err} is 0 and @var{msg} is an empty string.\n\
Otherwise, @var{err} is nonzero and @var{msg} contains a\n\
system-dependent error message.\n\
@end deftypefn")
{
  octave_value_list retval;

  retval(1) = std::string ();
  retval(0) = -1;

  int nargin = args.length ();

  if (nargin == 3)
    {
      octave_stream strm = octave_stream_list::lookup (args (0), "fcntl");

      if (! error_state)
        {
          int fid = strm.file_number ();

          int req = args(1).int_value (true);
          int arg = args(2).int_value (true);

          if (! error_state)
            {
              // FIXME -- Need better checking here?
              if (fid < 0)
                error ("fcntl: invalid file id");
              else
                {
                  std::string msg;

                  int status = octave_fcntl (fid, req, arg, msg);

                  retval(0) = status;
                  retval(1) = msg;
                }
            }
        }
      else
        error ("fcntl: file id, request, and argument must be integers");
    }
  else
    print_usage ();

  return retval;
}

DEFUNX ("fork", Ffork, args, ,
 "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {[@var{pid}, @var{msg}] =} fork ()\n\
Create a copy of the current process.\n\
\n\
Fork can return one of the following values:\n\
\n\
@table @asis\n\
@item > 0\n\
You are in the parent process.  The value returned from @code{fork} is\n\
the process id of the child process.  You should probably arrange to\n\
wait for any child processes to exit.\n\
\n\
@item 0\n\
You are in the child process.  You can call @code{exec} to start another\n\
process.  If that fails, you should probably call @code{exit}.\n\
\n\
@item < 0\n\
The call to @code{fork} failed for some reason.  You must take evasive\n\
action.  A system dependent error message will be waiting in @var{msg}.\n\
@end table\n\
@end deftypefn")
{
  octave_value_list retval;

  retval(1) = std::string ();
  retval(0) = -1;

  int nargin = args.length ();

  if (nargin == 0)
    {
      std::string msg;

      pid_t pid = octave_syscalls::fork (msg);

      retval(0) = pid;
      retval(1) = msg;
    }
  else
    print_usage ();

  return retval;
}

DEFUNX ("getpgrp", Fgetpgrp, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {pgid =} getpgrp ()\n\
Return the process group id of the current process.\n\
@end deftypefn")
{
  octave_value_list retval;

  retval(1) = std::string ();
  retval(0) = -1;

  int nargin = args.length ();

  if (nargin == 0)
    {
      std::string msg;

      retval(0) = octave_syscalls::getpgrp (msg);
      retval(1) = msg;
    }
  else
    print_usage ();

  return retval;
}

DEFUNX ("getpid", Fgetpid, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {pid =} getpid ()\n\
Return the process id of the current process.\n\
@end deftypefn")
{
  octave_value retval = -1;

  int nargin = args.length ();

  if (nargin == 0)
    retval = octave_syscalls::getpid ();
  else
    print_usage ();

  return retval;
}

DEFUNX ("getppid", Fgetppid, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {pid =} getppid ()\n\
Return the process id of the parent process.\n\
@end deftypefn")
{
  octave_value retval = -1;

  int nargin = args.length ();

  if (nargin == 0)
    retval = octave_syscalls::getppid ();
  else
    print_usage ();

  return retval;
}

DEFUNX ("getegid", Fgetegid, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {egid =} getegid ()\n\
Return the effective group id of the current process.\n\
@end deftypefn")
{
  octave_value retval = -1;

  int nargin = args.length ();

  if (nargin == 0)
    retval = octave_syscalls::getegid ();
  else
    print_usage ();

  return retval;
}

DEFUNX ("getgid", Fgetgid, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {gid =} getgid ()\n\
Return the real group id of the current process.\n\
@end deftypefn")
{
  octave_value retval = -1;

  int nargin = args.length ();

  if (nargin == 0)
    retval = octave_syscalls::getgid ();
  else
    print_usage ();

  return retval;
}

DEFUNX ("geteuid", Fgeteuid, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {euid =} geteuid ()\n\
Return the effective user id of the current process.\n\
@end deftypefn")
{
  octave_value retval = -1;

  int nargin = args.length ();

  if (nargin == 0)
    retval = octave_syscalls::geteuid ();
  else
    print_usage ();

  return retval;
}

DEFUNX ("getuid", Fgetuid, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {uid =} getuid ()\n\
Return the real user id of the current process.\n\
@end deftypefn")
{
  octave_value retval = -1;

  int nargin = args.length ();

  if (nargin == 0)
    retval = octave_syscalls::getuid ();
  else
    print_usage ();

  return retval;
}

DEFUNX ("kill", Fkill, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {[@var{err}, @var{msg}] =} kill (@var{pid}, @var{sig})\n\
Send signal @var{sig} to process @var{pid}.\n\
\n\
If @var{pid} is positive, then signal @var{sig} is sent to @var{pid}.\n\
\n\
If @var{pid} is 0, then signal @var{sig} is sent to every process\n\
in the process group of the current process.\n\
\n\
If @var{pid} is -1, then signal @var{sig} is sent to every process\n\
except process 1.\n\
\n\
If @var{pid} is less than -1, then signal @var{sig} is sent to every\n\
process in the process group @var{-pid}.\n\
\n\
If @var{sig} is 0, then no signal is sent, but error checking is still\n\
performed.\n\
\n\
Return 0 if successful, otherwise return -1.\n\
@end deftypefn")
{
  octave_value_list retval;

  retval(1) = std::string ();
  retval(0) = -1;

  if (args.length () == 2)
    {
      pid_t pid = args(0).int_value (true);

      if (! error_state)
        {
          int sig = args(1).int_value (true);

          if (! error_state)
            {
              std::string msg;

              int status = octave_syscalls::kill (pid, sig, msg);

              retval(1) = msg;
              retval(0) = status;
            }
        }
    }
  else
    print_usage ();

  return retval;
}

DEFUNX ("lstat", Flstat, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {[@var{info}, @var{err}, @var{msg}] =} lstat (@var{file})\n\
See stat.\n\
@end deftypefn")
{
  octave_value_list retval;

  if (args.length () == 1)
    {
      std::string fname = args(0).string_value ();

      if (! error_state)
        {
          file_stat fs (fname, false);

          retval = mk_stat_result (fs);
        }
    }
  else
    print_usage ();

  return retval;
}

DEFUNX ("mkfifo", Fmkfifo, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {[@var{err}, @var{msg}] =} mkfifo (@var{name}, @var{mode})\n\
Create a @var{fifo} special file named @var{name} with file mode @var{mode}\n\
\n\
If successful, @var{err} is 0 and @var{msg} is an empty string.\n\
Otherwise, @var{err} is nonzero and @var{msg} contains a\n\
system-dependent error message.\n\
@end deftypefn")
{
  octave_value_list retval;

  retval(1) = std::string ();
  retval(0) = -1;

  int nargin = args.length ();

  if (nargin == 2)
    {
      if (args(0).is_string ())
        {
          std::string name = args(0).string_value ();

          if (args(1).is_scalar_type ())
            {
              long mode = args(1).long_value ();

              if (! error_state)
                {
                  std::string msg;

                  int status = octave_mkfifo (name, mode, msg);

                  retval(0) = status;

                  if (status < 0)
                    retval(1) = msg;
                }
              else
                error ("mkfifo: invalid MODE");
            }
          else
            error ("mkfifo: MODE must be an integer");
        }
      else
        error ("mkfifo: file name must be a string");
    }
  else
    print_usage ();

  return retval;
}

DEFUNX ("pipe", Fpipe, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {[@var{read_fd}, @var{write_fd}, @var{err}, @var{msg}] =} pipe ()\n\
Create a pipe and return the reading and writing ends of the pipe\n\
into @var{read_fd} and @var{write_fd} respectively.\n\
\n\
If successful, @var{err} is 0 and @var{msg} is an empty string.\n\
Otherwise, @var{err} is nonzero and @var{msg} contains a\n\
system-dependent error message.\n\
@end deftypefn")
{
  octave_value_list retval;

  retval(3) = std::string ();
  retval(2) = -1;
  retval(1) = -1;
  retval(0) = -1;

  int nargin = args.length ();

  if (nargin == 0)
    {
      int fid[2];

      std::string msg;

      int status = octave_syscalls::pipe (fid, msg);

      if (status < 0)
        retval(3) = msg;
      else
        {
          FILE *ifile = fdopen (fid[0], "r");
          FILE *ofile = fdopen (fid[1], "w");

          std::string nm;

          octave_stream is = octave_stdiostream::create (nm, ifile,
                                                         std::ios::in);

          octave_stream os = octave_stdiostream::create (nm, ofile,
                                                         std::ios::out);

          retval(1) = octave_stream_list::insert (os);
          retval(0) = octave_stream_list::insert (is);

          retval(2) = status;
        }
    }
  else
    print_usage ();

  return retval;
}

DEFUNX ("stat", Fstat, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {[@var{info}, @var{err}, @var{msg}] =} stat (@var{file})\n\
@deftypefnx {Built-in Function} {[@var{info}, @var{err}, @var{msg}] =} lstat (@var{file})\n\
Return a structure @var{s} containing the following information about\n\
@var{file}.\n\
\n\
@table @code\n\
@item dev\n\
ID of device containing a directory entry for this file.\n\
\n\
@item ino\n\
File number of the file.\n\
\n\
@item mode\n\
File mode, as an integer.  Use the functions @w{@code{S_ISREG}},\n\
@w{@code{S_ISDIR}}, @w{@code{S_ISCHR}}, @w{@code{S_ISBLK}}, @w{@code{S_ISFIFO}},\n\
@w{@code{S_ISLNK}}, or @w{@code{S_ISSOCK}} to extract information from this\n\
value.\n\
\n\
@item modestr\n\
File mode, as a string of ten letters or dashes as would be returned by\n\
@kbd{ls -l}.\n\
\n\
@item nlink\n\
Number of links.\n\
\n\
@item uid\n\
User ID of file's owner.\n\
\n\
@item gid\n\
Group ID of file's group.\n\
\n\
@item rdev\n\
ID of device for block or character special files.\n\
\n\
@item size\n\
Size in bytes.\n\
\n\
@item atime\n\
Time of last access in the same form as time values returned from\n\
@code{time}.  @xref{Timing Utilities}.\n\
\n\
@item mtime\n\
Time of last modification in the same form as time values returned from\n\
@code{time}.  @xref{Timing Utilities}.\n\
\n\
@item ctime\n\
Time of last file status change in the same form as time values\n\
returned from @code{time}.  @xref{Timing Utilities}.\n\
\n\
@item blksize\n\
Size of blocks in the file.\n\
\n\
@item blocks\n\
Number of blocks allocated for file.\n\
@end table\n\
\n\
If the call is successful @var{err} is 0 and @var{msg} is an empty\n\
string.  If the file does not exist, or some other error occurs, @var{s}\n\
is an empty matrix, @var{err} is @minus{}1, and @var{msg} contains the\n\
corresponding system error message.\n\
\n\
If @var{file} is a symbolic link, @code{stat} will return information\n\
about the actual file that is referenced by the link.  Use @code{lstat}\n\
if you want information about the symbolic link itself.\n\
\n\
For example,\n\
\n\
@example\n\
[s, err, msg] = stat (\"/vmlinuz\")\n\
      @result{} s =\n\
        @{\n\
          atime = 855399756\n\
          rdev = 0\n\
          ctime = 847219094\n\
          uid = 0\n\
          size = 389218\n\
          blksize = 4096\n\
          mtime = 847219094\n\
          gid = 6\n\
          nlink = 1\n\
          blocks = 768\n\
          mode = -rw-r--r--\n\
          modestr = -rw-r--r--\n\
          ino = 9316\n\
          dev = 2049\n\
        @}\n\
     @result{} err = 0\n\
     @result{} msg = \n\
@end example\n\
@end deftypefn")
{
  octave_value_list retval;

  if (args.length () == 1)
    {
      if (args(0).is_scalar_type ())
        {
          int fid = octave_stream_list::get_file_number (args(0));

          if (! error_state)
            {
              file_fstat fs (fid);

              retval = mk_stat_result (fs);
            }
        }
      else
        {
          std::string fname = args(0).string_value ();

          if (! error_state)
            {
              file_stat fs (fname);

              retval = mk_stat_result (fs);
            }
        }
    }
  else
    print_usage ();

  return retval;
}

DEFUNX ("S_ISREG", FS_ISREG, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} S_ISREG (@var{mode})\n\
Return true if @var{mode} corresponds to a regular file.  The value\n\
of @var{mode} is assumed to be returned from a call to @code{stat}.\n\
@seealso{stat, lstat}\n\
@end deftypefn")
{
  octave_value retval = false;

  if (args.length () == 1)
    {
      double mode = args(0).double_value ();

      if (! error_state)
        retval = file_stat::is_reg (static_cast<mode_t> (mode));
      else
        error ("S_ISREG: invalid mode value");
    }
  else
    print_usage ();

  return retval;
}

DEFUNX ("S_ISDIR", FS_ISDIR, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} S_ISDIR (@var{mode})\n\
Return true if @var{mode} corresponds to a directory.  The value\n\
of @var{mode} is assumed to be returned from a call to @code{stat}.\n\
@seealso{stat, lstat}\n\
@end deftypefn")
{
  octave_value retval = false;

  if (args.length () == 1)
    {
      double mode = args(0).double_value ();

      if (! error_state)
        retval = file_stat::is_dir (static_cast<mode_t> (mode));
      else
        error ("S_ISDIR: invalid mode value");
    }
  else
    print_usage ();

  return retval;
}

DEFUNX ("S_ISCHR", FS_ISCHR, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} S_ISCHR (@var{mode})\n\
Return true if @var{mode} corresponds to a character devicey.  The value\n\
of @var{mode} is assumed to be returned from a call to @code{stat}.\n\
@seealso{stat, lstat}\n\
@end deftypefn")
{
  octave_value retval = false;

  if (args.length () == 1)
    {
      double mode = args(0).double_value ();

      if (! error_state)
        retval = file_stat::is_chr (static_cast<mode_t> (mode));
      else
        error ("S_ISCHR: invalid mode value");
    }
  else
    print_usage ();

  return retval;
}

DEFUNX ("S_ISBLK", FS_ISBLK, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} S_ISBLK (@var{mode})\n\
Return true if @var{mode} corresponds to a block device.  The value\n\
of @var{mode} is assumed to be returned from a call to @code{stat}.\n\
@seealso{stat, lstat}\n\
@end deftypefn")
{
  octave_value retval = false;

  if (args.length () == 1)
    {
      double mode = args(0).double_value ();

      if (! error_state)
        retval = file_stat::is_blk (static_cast<mode_t> (mode));
      else
        error ("S_ISBLK: invalid mode value");
    }
  else
    print_usage ();

  return retval;
}

DEFUNX ("S_ISFIFO", FS_ISFIFO, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} S_ISFIFO (@var{mode})\n\
Return true if @var{mode} corresponds to a fifo.  The value\n\
of @var{mode} is assumed to be returned from a call to @code{stat}.\n\
@seealso{stat, lstat}\n\
@end deftypefn")
{
  octave_value retval = false;

  if (args.length () == 1)
    {
      double mode = args(0).double_value ();

      if (! error_state)
        retval = file_stat::is_fifo (static_cast<mode_t> (mode));
      else
        error ("S_ISFIFO: invalid mode value");
    }
  else
    print_usage ();

  return retval;
}

DEFUNX ("S_ISLNK", FS_ISLNK, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} S_ISLNK (@var{mode})\n\
Return true if @var{mode} corresponds to a symbolic link.  The value\n\
of @var{mode} is assumed to be returned from a call to @code{stat}.\n\
@seealso{stat, lstat}\n\
@end deftypefn")
{
  octave_value retval = false;

  if (args.length () == 1)
    {
      double mode = args(0).double_value ();

      if (! error_state)
        retval = file_stat::is_lnk (static_cast<mode_t> (mode));
      else
        error ("S_ISLNK: invalid mode value");
    }
  else
    print_usage ();

  return retval;
}

DEFUNX ("S_ISSOCK", FS_ISSOCK, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} S_ISSOCK (@var{mode})\n\
@seealso{stat, lstat}\n\
@end deftypefn")
{
  octave_value retval = false;

  if (args.length () == 1)
    {
      double mode = args(0).double_value ();

      if (! error_state)
        retval = file_stat::is_sock (static_cast<mode_t> (mode));
      else
        error ("S_ISSOCK: invalid mode value");
    }
  else
    print_usage ();

  return retval;
}

DEFUN (uname, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {[@var{uts}, @var{err}, @var{msg}] =} uname ()\n\
Return system information in the structure.  For example,\n\
\n\
@example\n\
@group\n\
uname ()\n\
     @result{} @{\n\
           sysname = x86_64\n\
           nodename = segfault\n\
           release = 2.6.15-1-amd64-k8-smp\n\
           version = Linux\n\
           machine = #2 SMP Thu Feb 23 04:57:49 UTC 2006\n\
         @}\n\
@end group\n\
@end example\n\
\n\
If successful, @var{err} is 0 and @var{msg} is an empty string.\n\
Otherwise, @var{err} is nonzero and @var{msg} contains a\n\
system-dependent error message.\n\
@end deftypefn")
{
  octave_value_list retval;

  if (args.length () == 0)
    {
      octave_uname sysinfo;

      octave_scalar_map m;

      m.assign ("sysname", sysinfo.sysname ());
      m.assign ("nodename", sysinfo.nodename ());
      m.assign ("release", sysinfo.release ());
      m.assign ("version", sysinfo.version ());
      m.assign ("machine", sysinfo.machine ());

      retval(2) = sysinfo.message ();
      retval(1) = sysinfo.error ();
      retval(0) = m;
    }
  else
    print_usage ();

  return retval;
}

DEFUNX ("unlink", Funlink, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {[@var{err}, @var{msg}] =} unlink (@var{file})\n\
Delete the file named @var{file}.\n\
\n\
If successful, @var{err} is 0 and @var{msg} is an empty string.\n\
Otherwise, @var{err} is nonzero and @var{msg} contains a\n\
system-dependent error message.\n\
@end deftypefn")
{
  octave_value_list retval;

  retval(1) = std::string ();
  retval(0) = -1;

  int nargin = args.length ();

  if (nargin == 1)
    {
      if (args(0).is_string ())
        {
          std::string name = args(0).string_value ();

          std::string msg;

          int status = octave_unlink (name, msg);

          retval(0) = status;
          retval(1) = msg;          
        }
      else
        error ("unlink: file name must be a string");
    }
  else
    print_usage ();

  return retval;
}

DEFUNX ("waitpid", Fwaitpid, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {[@var{pid}, @var{status}, @var{msg}] =} waitpid (@var{pid}, @var{options})\n\
Wait for process @var{pid} to terminate.  The @var{pid} argument can be:\n\
\n\
@table @asis\n\
@item @minus{}1\n\
Wait for any child process.\n\
\n\
@item 0\n\
Wait for any child process whose process group ID is equal to that of\n\
the Octave interpreter process.\n\
\n\
@item > 0\n\
Wait for termination of the child process with ID @var{pid}.\n\
@end table\n\
\n\
The @var{options} argument can be a bitwise OR of zero or more of\n\
the following constants:\n\
\n\
@table @code\n\
@item 0\n\
Wait until signal is received or a child process exits (this is the\n\
default if the @var{options} argument is missing).\n\
\n\
@item WNOHANG\n\
Do not hang if status is not immediately available.\n\
\n\
@item WUNTRACED\n\
Report the status of any child processes that are stopped, and whose\n\
status has not yet been reported since they stopped.\n\
\n\
@item WCONTINUE\n\
Return if a stopped child has been resumed by delivery of @code{SIGCONT}.\n\
This value may not be meaningful on all systems.\n\
@end table\n\
\n\
If the returned value of @var{pid} is greater than 0, it is the process\n\
ID of the child process that exited.  If an error occurs, @var{pid} will\n\
be less than zero and @var{msg} will contain a system-dependent error\n\
message.  The value of @var{status} contains additional system-dependent\n\
information about the subprocess that exited.\n\
@seealso{WCONTINUE, WCOREDUMP, WEXITSTATUS, WIFCONTINUED, WIFSIGNALED, WIFSTOPPED, WNOHANG, WSTOPSIG, WTERMSIG, WUNTRACED}\n\
@end deftypefn")
{
  octave_value_list retval;

  retval(2) = std::string ();
  retval(1) = 0;
  retval(0) = -1;

  int nargin = args.length ();

  if (nargin == 1 || nargin == 2)
    {
      pid_t pid = args(0).int_value (true);
  
      if (! error_state)
        {
          int options = 0;

          if (args.length () == 2)
            options = args(1).int_value (true);

          if (! error_state)
            {
              std::string msg;

              int status = 0;

              pid_t result = octave_syscalls::waitpid (pid, &status, options, msg);

              retval(0) = result;
              retval(1) = status;
              retval(2) = msg;
            }
          else
            error ("waitpid: OPTIONS must be an integer");
        }
      else
        error ("waitpid: PID must be an integer value");
    }
  else
    print_usage ();

  return retval;
}

DEFUNX ("WIFEXITED", FWIFEXITED, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} WIFEXITED (@var{status})\n\
Given @var{status} from a call to @code{waitpid}, return true if the\n\
child terminated normally.\n\
@seealso{waitpid, WEXITSTATUS, WIFSIGNALED, WTERMSIG, WCOREDUMP, WIFSTOPPED, WSTOPSIG, WIFCONTINUED}\n\
@end deftypefn")
{
  octave_value retval = 0.0;

#if defined (WIFEXITED)
  if (args.length () == 1)
    {
      int status = args(0).int_value ();

      if (! error_state)
        retval = WIFEXITED (status);
      else
        error ("WIFEXITED: expecting integer argument");
    }
#else
  warning ("WIFEXITED always returns false in this version of Octave")
#endif

  return retval;
}

DEFUNX ("WEXITSTATUS", FWEXITSTATUS, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} WEXITSTATUS (@var{status})\n\
Given @var{status} from a call to @code{waitpid}, return the exit\n\
status of the child.  This function should only be employed if\n\
@code{WIFEXITED} returned true.\n\
@seealso{waitpid, WIFEXITED, WIFSIGNALED, WTERMSIG, WCOREDUMP, WIFSTOPPED, WSTOPSIG, WIFCONTINUED}\n\
@end deftypefn")
{
  octave_value retval = 0.0;

#if defined (WEXITSTATUS)
  if (args.length () == 1)
    {
      int status = args(0).int_value ();

      if (! error_state)
        retval = WEXITSTATUS (status);
      else
        error ("WEXITSTATUS: expecting integer argument");
    }
#else
  warning ("WEXITSTATUS always returns false in this version of Octave")
#endif

  return retval;
}

DEFUNX ("WIFSIGNALED", FWIFSIGNALED, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} WIFSIGNALED (@var{status})\n\
Given @var{status} from a call to @code{waitpid}, return true if the\n\
child process was terminated by a signal.\n\
@seealso{waitpid, WIFEXITED, WEXITSTATUS, WTERMSIG, WCOREDUMP, WIFSTOPPED, WSTOPSIG, WIFCONTINUED}\n\
@end deftypefn")
{
  octave_value retval = 0.0;

#if defined (WIFSIGNALED)
  if (args.length () == 1)
    {
      int status = args(0).int_value ();

      if (! error_state)
        retval = WIFSIGNALED (status);
      else
        error ("WIFSIGNALED: expecting integer argument");
    }
#else
  warning ("WIFSIGNALED always returns false in this version of Octave");
#endif

  return retval;
}

DEFUNX ("WTERMSIG", FWTERMSIG, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} WTERMSIG (@var{status})\n\
Given @var{status} from a call to @code{waitpid}, return the number of\n\
the signal that caused the child process to terminate.  This function\n\
should only be employed if @code{WIFSIGNALED} returned true.\n\
@seealso{waitpid, WIFEXITED, WEXITSTATUS, WIFSIGNALED, WCOREDUMP, WIFSTOPPED, WSTOPSIG, WIFCONTINUED}\n\
@end deftypefn")
{
  octave_value retval = 0.0;

#if defined (WTERMSIG)
  if (args.length () == 1)
    {
      int status = args(0).int_value ();

      if (! error_state)
        retval = WTERMSIG (status);
      else
        error ("WTERMSIG: expecting integer argument");
    }
#else
  warning ("WTERMSIG always returns false in this version of Octave");
#endif

  return retval;
}

DEFUNX ("WCOREDUMP", FWCOREDUMP, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} WCOREDUMP (@var{status})\n\
Given @var{status} from a call to @code{waitpid}, return true if the\n\
child produced a core dump.  This function should only be employed if\n\
@code{WIFSIGNALED} returned true.  The macro used to implement this\n\
function is not specified in POSIX.1-2001 and is not available on some\n\
Unix implementations (e.g., AIX, SunOS).\n\
@seealso{waitpid, WIFEXITED, WEXITSTATUS, WIFSIGNALED, WTERMSIG, WIFSTOPPED, WSTOPSIG, WIFCONTINUED}\n\
@end deftypefn")
{
  octave_value retval = 0.0;

#if defined (WCOREDUMP)
  if (args.length () == 1)
    {
      int status = args(0).int_value ();

      if (! error_state)
        retval = WCOREDUMP (status);
      else
        error ("WCOREDUMP: expecting integer argument");
    }
#else
  warning ("WCOREDUMP always returns false in this version of Octave");
#endif

  return retval;
}

DEFUNX ("WIFSTOPPED", FWIFSTOPPED, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} WIFSTOPPED (@var{status})\n\
Given @var{status} from a call to @code{waitpid}, return true if the\n\
child process was stopped by delivery of a signal; this is only\n\
possible if the call was done using @code{WUNTRACED} or when the child\n\
is being traced (see ptrace(2)).\n\
@seealso{waitpid, WIFEXITED, WEXITSTATUS, WIFSIGNALED, WTERMSIG, WCOREDUMP, WSTOPSIG, WIFCONTINUED}\n\
@end deftypefn")
{
  octave_value retval = 0.0;

#if defined (WIFSTOPPED)
  if (args.length () == 1)
    {
      int status = args(0).int_value ();

      if (! error_state)
        retval = WIFSTOPPED (status);
      else
        error ("WIFSTOPPED: expecting integer argument");
    }
#else
  warning ("WIFSTOPPED always returns false in this version of Octave");
#endif

  return retval;
}

DEFUNX ("WSTOPSIG", FWSTOPSIG, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} WSTOPSIG (@var{status})\n\
Given @var{status} from a call to @code{waitpid}, return the number of\n\
the signal which caused the child to stop.  This function should only\n\
be employed if @code{WIFSTOPPED} returned true.\n\
@seealso{waitpid, WIFEXITED, WEXITSTATUS, WIFSIGNALED, WTERMSIG, WCOREDUMP, WIFSTOPPED, WIFCONTINUED}\n\
@end deftypefn")
{
  octave_value retval = 0.0;

#if defined (WSTOPSIG)
  if (args.length () == 1)
    {
      int status = args(0).int_value ();

      if (! error_state)
        retval = WSTOPSIG (status);
      else
        error ("WSTOPSIG: expecting integer argument");
    }
#else
  warning ("WSTOPSIG always returns false in this version of Octave");
#endif

  return retval;
}

DEFUNX ("WIFCONTINUED", FWIFCONTINUED, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} WIFCONTINUED (@var{status})\n\
Given @var{status} from a call to @code{waitpid}, return true if the\n\
child process was resumed by delivery of @code{SIGCONT}.\n\
@seealso{waitpid, WIFEXITED, WEXITSTATUS, WIFSIGNALED, WTERMSIG, WCOREDUMP, WIFSTOPPED, WSTOPSIG}\n\
@end deftypefn")
{
  octave_value retval = 0.0;

#if defined (WIFCONTINUED)
  if (args.length () == 1)
    {
      int status = args(0).int_value ();

      if (! error_state)
        retval = WIFCONTINUED (status);
      else
        error ("WIFCONTINUED: expecting integer argument");
    }
#else
  warning ("WIFCONTINUED always returns false in this version of Octave");
#endif

  return retval;
}

DEFUNX ("canonicalize_file_name", Fcanonicalize_file_name, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {[@var{cname}, @var{status}, @var{msg}]} canonicalize_file_name (@var{name})\n\
Return the canonical name of file @var{name}.\n\
@end deftypefn")
{
  octave_value_list retval;

  if (args.length () == 1)
    {
      std::string name = args(0).string_value ();

      if (! error_state)
        {
          std::string msg;

          std::string result = octave_canonicalize_file_name (name, msg);

          retval(2) = msg;
          retval(1) = msg.empty () ? 0 : -1;
          retval(0) = result;
        }
      else
        error ("canonicalize_file_name: argument must be a character string");
    }
  else
    print_usage ();

  return retval;
}

static octave_value
const_value (const octave_value_list& args, int val)
{
  octave_value retval;

  int nargin = args.length ();

  if (nargin == 0)
    retval = val;
  else
    print_usage ();

  return retval;
}

#if !defined (O_NONBLOCK) && defined (O_NDELAY)
#define O_NONBLOCK O_NDELAY
#endif

#if defined (F_DUPFD)
DEFUNX ("F_DUPFD", FF_DUPFD, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} F_DUPFD ()\n\
Return the value required to request that @code{fcntl} return a\n\
duplicate file descriptor.\n\
@seealso{fcntl, F_GETFD, F_GETFL, F_SETFD, F_SETFL}\n\
@end deftypefn")
{
  return const_value (args, F_DUPFD);
}
#endif

#if defined (F_GETFD)
DEFUNX ("F_GETFD", FF_GETFD, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} F_GETFD ()\n\
Return the value required to request that @code{fcntl} to return the\n\
file descriptor flags.\n\
@seealso{fcntl, F_DUPFD, F_GETFL, F_SETFD, F_SETFL}\n\
@end deftypefn")
{
  return const_value (args, F_GETFD);
}
#endif

#if defined (F_GETFL)
DEFUNX ("F_GETFL", FF_GETFL, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} F_GETFL ()\n\
Return the value required to request that @code{fcntl} to return the\n\
file status flags.\n\
@seealso{fcntl, F_DUPFD, F_GETFD, F_SETFD, F_SETFL}\n\
@end deftypefn")
{
  return const_value (args, F_GETFL);
}
#endif

#if defined (F_SETFD)
DEFUNX ("F_SETFD", FF_SETFD, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} F_SETFD ()\n\
Return the value required to request that @code{fcntl} to set the file\n\
descriptor flags.\n\
@seealso{fcntl, F_DUPFD, F_GETFD, F_GETFL, F_SETFL}\n\
@end deftypefn")
{
  return const_value (args, F_SETFD);
}
#endif

#if defined (F_SETFL)
DEFUNX ("F_SETFL", FF_SETFL, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} F_SETFL ()\n\
Return the value required to request that @code{fcntl} to set the file\n\
status flags.\n\
@seealso{fcntl, F_DUPFD, F_GETFD, F_GETFL, F_SETFD}\n\
@end deftypefn")
{
  return const_value (args, F_SETFL);
}
#endif

#if defined (O_APPEND)
DEFUNX ("O_APPEND", FO_APPEND, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} O_APPEND ()\n\
Return the numerical value of the file status flag that may be\n\
returned by @code{fcntl} to indicate each write operation appends,\n\
or that may be passed to @code{fcntl} to set the write mode to append.\\n\
@seealso{fcntl, O_ASYNC, O_CREAT, O_EXCL, O_NONBLOCK, O_RDONLY, O_RDWR, O_SYNC, O_TRUNC, O_WRONLY}\n\
@end deftypefn")
{
  return const_value (args, O_APPEND);
}
#endif

#if defined (O_ASYNC)
DEFUNX ("O_ASYNC", FO_ASYNC, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} O_ASYNC ()\n\
Return the numerical value of the file status flag that may be\n\
returned by @code{fcntl} to indicate asynchronous I/O.\n\
@seealso{fcntl, O_APPEND, O_CREAT, O_EXCL, O_NONBLOCK, O_RDONLY, O_RDWR, O_SYNC, O_TRUNC, O_WRONLY}\n\
@end deftypefn")
{
  return const_value (args, O_ASYNC);
}
#endif

#if defined (O_CREAT)
DEFUNX ("O_CREAT", FO_CREAT, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} O_CREAT ()\n\
Return the numerical value of the file status flag that may be\n\
returned by @code{fcntl} to indicate that a file should be\n\
created if it does not exist.\n\
@seealso{fcntl, O_APPEND, O_ASYNC, O_EXCL, O_NONBLOCK, O_RDONLY, O_RDWR, O_SYNC, O_TRUNC, O_WRONLY}\n\
@end deftypefn")
{
  return const_value (args, O_CREAT);
}
#endif

#if defined (O_EXCL)
DEFUNX ("O_EXCL", FO_EXCL, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} O_EXCL ()\n\
Return the numerical value of the file status flag that may be\n\
returned by @code{fcntl} to indicate that file locking is used.\n\
@seealso{fcntl, O_APPEND, O_ASYNC, O_CREAT, O_NONBLOCK, O_RDONLY, O_RDWR, O_SYNC, O_TRUNC, O_WRONLY}\n\
@end deftypefn")
{
  return const_value (args, O_EXCL);
}
#endif

#if defined (O_NONBLOCK)
DEFUNX ("O_NONBLOCK", FO_NONBLOCK, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} O_NONBLOCK ()\n\
Return the numerical value of the file status flag that may be\n\
returned by @code{fcntl} to indicate that non-blocking I/O is in use,\n\
or that may be passsed to @code{fcntl} to set non-blocking I/O.\n\
@seealso{fcntl, O_APPEND, O_ASYNC, O_CREAT, O_EXCL, O_RDONLY, O_RDWR, O_SYNC, O_TRUNC, O_WRONLY}\n\
@end deftypefn")
{
  return const_value (args, O_NONBLOCK);
}
#endif

#if defined (O_RDONLY)
DEFUNX ("O_RDONLY", FO_RDONLY, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} O_RDONLY ()\n\
Return the numerical value of the file status flag that may be\n\
returned by @code{fcntl} to indicate that a file is open for\n\
reading only.\n\
@seealso{fcntl, O_APPEND, O_ASYNC, O_CREAT, O_EXCL, O_NONBLOCK, O_RDWR, O_SYNC, O_TRUNC, O_WRONLY}\n\
@end deftypefn")
{
  return const_value (args, O_RDONLY);
}
#endif

#if defined (O_RDWR)
DEFUNX ("O_RDWR", FO_RDWR, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} O_RDWR ()\n\
Return the numerical value of the file status flag that may be\n\
returned by @code{fcntl} to indicate that a file is open for both\n\
reading and writing.\n\
@seealso{fcntl, O_APPEND, O_ASYNC, O_CREAT, O_EXCL, O_NONBLOCK, O_RDONLY, O_SYNC, O_TRUNC, O_WRONLY}\n\
@end deftypefn")
{
  return const_value (args, O_RDWR);
}
#endif

#if defined (O_SYNC)
DEFUNX ("O_SYNC", FO_SYNC, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} O_SYNC ()\n\
Return the numerical value of the file status flag that may be\n\
returned by @code{fcntl} to indicate that a file is open for\n\
synchronous I/O.\n\
@seealso{fcntl, O_APPEND, O_ASYNC, O_CREAT, O_EXCL, O_NONBLOCK, O_RDONLY, O_RDWR, O_TRUNC, O_WRONLY}\n\
@end deftypefn")
{
  return const_value (args, O_SYNC);
}
#endif

#if defined (O_TRUNC)
DEFUNX ("O_TRUNC", FO_TRUNC, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Variable} O_TRUNC ()\n\
Return the numerical value of the file status flag that may be\n\
returned by @code{fcntl} to indicate that if file exists, it should\n\
be truncated when writing.\n\
@seealso{fcntl, O_APPEND, O_ASYNC, O_CREAT, O_EXCL, O_NONBLOCK, O_RDONLY, O_RDWR, O_SYNC, O_WRONLY}\n\
@end deftypefn")
{
  return const_value (args, O_TRUNC);
}
#endif

#if defined (O_WRONLY)
DEFUNX ("O_WRONLY", FO_WRONLY, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} O_WRONLY ()\n\
Return the numerical value of the file status flag that may be\n\
returned by @code{fcntl} to indicate that a file is open for\n\
writing only.\n\
@seealso{fcntl, O_APPEND, O_ASYNC, O_CREAT, O_EXCL, O_NONBLOCK, O_RDONLY, O_RDWR, O_SYNC, O_TRUNC}\n\
@end deftypefn")
{
  return const_value (args, O_WRONLY);
}
#endif

#if !defined (WNOHANG)
#define WNOHANG 0
#endif

DEFUNX ("WNOHANG", FWNOHANG, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} WNOHANG ()\n\
Return the numerical value of the option argument that may be\n\
passed to @code{waitpid} to indicate that it should return its\n\
status immediately instead of waiting for a process to exit.\n\
@seealso{waitpid, WUNTRACED, WCONTINUE}\n\
@end deftypefn")
{
  return const_value (args, WNOHANG);
}

#if !defined (WUNTRACED)
#define WUNTRACED 0
#endif

DEFUNX ("WUNTRACED", FWUNTRACED, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} WUNTRACED ()\n\
Return the numerical value of the option argument that may be\n\
passed to @code{waitpid} to indicate that it should also return\n\
if the child process has stopped but is not traced via the\n\
@code{ptrace} system call\n\
@seealso{waitpid, WNOHANG, WCONTINUE}\n\
@end deftypefn")
{
  return const_value (args, WUNTRACED);
}

#if !defined (WCONTINUE)
#define WCONTINUE 0
#endif

DEFUNX ("WCONTINUE", FWCONTINUE, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} WCONTINUE ()\n\
Return the numerical value of the option argument that may be\n\
passed to @code{waitpid} to indicate that it should also return\n\
if a stopped child has been resumed by delivery of a @code{SIGCONT}\n\
signal.\n\
@seealso{waitpid, WNOHANG, WUNTRACED}\n\
@end deftypefn")
{
  return const_value (args, WCONTINUE);
}