Assume POSIX 1003.1-1988 or later for fcntl.h.

* admin/CPP-DEFINES (O_RDONLY, O_RDWR, HAVE_FCNTL_H): Remove.
* admin/merge-gnulib (GNULIB_MODULES): Add fcntl-h.
* configure.ac: Do not check for fcntl.h.
* lib/gnulib.mk: Regenerate.
* lib-src/movemail.c, lib-src/update-game-score.c: Assume <fcntl.h> exists.
* nt/inc/sys/socket.h (O_NONBLOCK): Rename from O_NDELAY, since the
POSIX name for this flag is O_NONBLOCK.  All uses changed.
* nt/inc/unistd.h (O_RDWR, O_NOCTTY): New macros.  Like AT_FDCWD etc.
these really should be moved to a replacement <fcntl.h> if and
when that gets implemented.  In the meantime, include <fcntl.h>
to make sure we don't override its definitions.
* src/callproc.c (relocate_fd): Assume F_DUPFD.
* src/emacs.c, src/term.c (O_RDWR): Remove.
* src/keyboard.c (tty_read_avail_input): Use O_NONBLOCK rather than
O_NDELAY, since O_NONBLOCK is the standard name for this flag.
* src/nsterm.m: Assume <fcntl.h> exists.
* src/process.c (NON_BLOCKING_CONNECT, allocate_pty, create_process)
(create_pty, Fmake_network_process, server_accept_connection)
(wait_reading_process_output, init_process_emacs):
Assume O_NONBLOCK.
(wait_reading_process_output): Put in a special case for WINDOWSNT
to mimick the older behavior where it had O_NDELAY but not O_NONBLOCK.
It's not clear this is needed, but it's a more-conservative change.
(create_process): Assume FD_CLOEXEC.
(create_process, create_pty): Assume O_NOCTTY.
* src/sysdep.c (init_sys_modes, reset_sys_modes): Assume F_SETFL.
(reset_sys_modes): Use O_NONBLOCK rather than O_NDELAY.
Omit if not DOS_NT, since F_GETFL is not defined there.
(serial_open): Assume O_NONBLOCK and O_NOCTTY.
* src/term.c: Include <fcntl.h>, for flags like O_NOCTTY.
(O_NOCTTY): Remove.
(init_tty): Assume O_IGNORE_CTTY is defined to 0 on platforms that
lack it, since gnulib guarantees this.
* src/w32.c (fcntl): Test for O_NONBLOCK rather than O_NDELAY.

Fixes: debbugs:12881

21 files changed, 101 insertions, 146 deletions

diff --git a/ChangeLog b/ChangeLog
index 1e5bf54a897..05e1a14d55d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2012-11-17  Paul Eggert  <eggert@cs.ucla.edu>
+
+        Assume POSIX 1003.1-1988 or later for fcntl.h (Bug#12881).
+        * configure.ac: Do not check for fcntl.h.
+        * lib/gnulib.mk: Regenerate.
+
 2012-11-16  Paul Eggert  <eggert@cs.ucla.edu>
 
         Remove no-longer-used pty_max_bytes variable.
diff --git a/admin/CPP-DEFINES b/admin/CPP-DEFINES
index 17c56dc7e9e..ae8673452a3 100644
--- a/admin/CPP-DEFINES
+++ b/admin/CPP-DEFINES
@@ -150,7 +150,6 @@ HAVE_ENDGRENT
 HAVE_ENDPWENT
 HAVE_ENVIRON_DECL
 HAVE_EUIDACCESS
-HAVE_FCNTL_H
 HAVE_FORK
 HAVE_FREEIFADDRS
 HAVE_FREETYPE
@@ -419,8 +418,6 @@ NSIG
 NSIG_MINIMUM
 NULL_DEVICE
 ORDINARY_LINK
-O_RDONLY
-O_RDWR
 PAGESIZE
 PREFER_VSUSP
 PTY_ITERATION
diff --git a/admin/ChangeLog b/admin/ChangeLog
index 4eb413e948f..3d76f9dd2ba 100644
--- a/admin/ChangeLog
+++ b/admin/ChangeLog
@@ -1,3 +1,9 @@
+2012-11-17  Paul Eggert  <eggert@cs.ucla.edu>
+
+        Assume POSIX 1003.1-1988 or later for fcntl.h (Bug#12881).
+        * CPP-DEFINES (O_RDONLY, O_RDWR, HAVE_FCNTL_H): Remove.
+        * merge-gnulib (GNULIB_MODULES): Add fcntl-h.
+
 2012-11-16  Paul Eggert  <eggert@cs.ucla.edu>
 
         Remove no-longer-used pty_max_bytes variable.
diff --git a/admin/merge-gnulib b/admin/merge-gnulib
index f7a675e5101..792818b2efe 100755
--- a/admin/merge-gnulib
+++ b/admin/merge-gnulib
@@ -29,7 +29,7 @@ GNULIB_MODULES='
   alloca-opt c-ctype c-strcase
   careadlinkat close-stream crypto/md5 crypto/sha1 crypto/sha256 crypto/sha512
   dtoastr dtotimespec dup2 environ execinfo faccessat
-  filemode getloadavg getopt-gnu gettime gettimeofday
+  fcntl-h filemode getloadavg getopt-gnu gettime gettimeofday
   ignore-value intprops largefile lstat
   manywarnings mktime pselect pthread_sigmask readlink
   socklen stat-time stdalign stdarg stdbool stdio
diff --git a/configure.ac b/configure.ac
index 937c645bb58..1884cc7ccf7 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1268,7 +1268,7 @@ fi
 dnl checks for header files
 AC_CHECK_HEADERS_ONCE(
   linux/version.h sys/systeminfo.h
-  fcntl.h coff.h pty.h
+  coff.h pty.h
   sys/vlimit.h sys/resource.h
   sys/utsname.h pwd.h utmp.h dirent.h util.h)
 
diff --git a/lib-src/ChangeLog b/lib-src/ChangeLog
index 03cddc6a035..599e005b4e0 100644
--- a/lib-src/ChangeLog
+++ b/lib-src/ChangeLog
@@ -1,3 +1,8 @@
+2012-11-17  Paul Eggert  <eggert@cs.ucla.edu>
+
+        Assume POSIX 1003.1-1988 or later for fcntl.h (Bug#12881).
+        * movemail.c, update-game-score.c: Assume <fcntl.h> exists.
+
 2012-10-26  Glenn Morris  <rgm@gnu.org>
 
         * Makefile.in (uninstall): No INSTALLABLES live in archlibdir.
diff --git a/lib-src/movemail.c b/lib-src/movemail.c
index 32d32e69abf..cd329a110a8 100644
--- a/lib-src/movemail.c
+++ b/lib-src/movemail.c
@@ -65,9 +65,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include <getopt.h>
 #include <unistd.h>
-#ifdef HAVE_FCNTL_H
 #include <fcntl.h>
-#endif
 #include <string.h>
 #include "syswait.h"
 #ifdef MAIL_USE_POP
diff --git a/lib-src/update-game-score.c b/lib-src/update-game-score.c
index 40397536fad..59cab61aa29 100644
--- a/lib-src/update-game-score.c
+++ b/lib-src/update-game-score.c
@@ -42,9 +42,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <time.h>
 #include <pwd.h>
 #include <ctype.h>
-#ifdef HAVE_FCNTL_H
 #include <fcntl.h>
-#endif
 #include <sys/stat.h>
 #include <getopt.h>
 
diff --git a/lib/gnulib.mk b/lib/gnulib.mk
index f74c46ae9c8..834f63169e2 100644
--- a/lib/gnulib.mk
+++ b/lib/gnulib.mk
@@ -21,7 +21,7 @@
 # the same distribution terms as the rest of that program.
 #
 # Generated by gnulib-tool.
-# Reproduce by: gnulib-tool --import --dir=. --lib=libgnu --source-base=lib --m4-base=m4 --doc-base=doc --tests-base=tests --aux-dir=build-aux --avoid=at-internal --avoid=errno --avoid=fchdir --avoid=fcntl --avoid=fstat --avoid=malloc-posix --avoid=msvc-inval --avoid=msvc-nothrow --avoid=openat-die --avoid=openat-h --avoid=raise --avoid=save-cwd --avoid=select --avoid=sigprocmask --avoid=sys_types --avoid=threadlib --makefile-name=gnulib.mk --conditional-dependencies --no-libtool --macro-prefix=gl --no-vc-files alloca-opt c-ctype c-strcase careadlinkat close-stream crypto/md5 crypto/sha1 crypto/sha256 crypto/sha512 dtoastr dtotimespec dup2 environ execinfo faccessat filemode getloadavg getopt-gnu gettime gettimeofday ignore-value intprops largefile lstat manywarnings mktime pselect pthread_sigmask readlink socklen stat-time stdalign stdarg stdbool stdio strftime strtoimax strtoumax symlink sys_stat sys_time time timer-time timespec-add timespec-sub utimens warnings
+# Reproduce by: gnulib-tool --import --dir=. --lib=libgnu --source-base=lib --m4-base=m4 --doc-base=doc --tests-base=tests --aux-dir=build-aux --avoid=at-internal --avoid=errno --avoid=fchdir --avoid=fcntl --avoid=fstat --avoid=malloc-posix --avoid=msvc-inval --avoid=msvc-nothrow --avoid=openat-die --avoid=openat-h --avoid=raise --avoid=save-cwd --avoid=select --avoid=sigprocmask --avoid=sys_types --avoid=threadlib --makefile-name=gnulib.mk --conditional-dependencies --no-libtool --macro-prefix=gl --no-vc-files alloca-opt c-ctype c-strcase careadlinkat close-stream crypto/md5 crypto/sha1 crypto/sha256 crypto/sha512 dtoastr dtotimespec dup2 environ execinfo faccessat fcntl-h filemode getloadavg getopt-gnu gettime gettimeofday ignore-value intprops largefile lstat manywarnings mktime pselect pthread_sigmask readlink socklen stat-time stdalign stdarg stdbool stdio strftime strtoimax strtoumax symlink sys_stat sys_time time timer-time timespec-add timespec-sub utimens warnings
 
 
 MOSTLYCLEANFILES += core *.stackdump
diff --git a/nt/ChangeLog b/nt/ChangeLog
index b24acae8be5..910ef2170c6 100644
--- a/nt/ChangeLog
+++ b/nt/ChangeLog
@@ -1,3 +1,13 @@
+2012-11-17  Paul Eggert  <eggert@cs.ucla.edu>
+
+        Assume POSIX 1003.1-1988 or later for fcntl.h (Bug#12881).
+        * inc/sys/socket.h (O_NONBLOCK): Rename from O_NDELAY, since the
+        POSIX name for this flag is O_NONBLOCK.  All uses changed.
+        * inc/unistd.h (O_RDWR, O_NOCTTY): New macros.  Like AT_FDCWD etc.
+        these really should be moved to a replacement <fcntl.h> if and
+        when that gets implemented.  In the meantime, include <fcntl.h>
+        to make sure we don't override its definitions.
+
 2012-11-17  Eli Zaretskii  <eliz@gnu.org>
 
         * inc/sys/wait.h: New file, with prototype of waitpid and
diff --git a/nt/inc/sys/socket.h b/nt/inc/sys/socket.h
index 70225a9c82f..95fee4c4659 100644
--- a/nt/inc/sys/socket.h
+++ b/nt/inc/sys/socket.h
@@ -119,7 +119,7 @@ int sys_sendto (int s, const char * buf, int len, int flags,
    an fcntl function, for setting sockets to non-blocking mode.  */
 int fcntl (int s, int cmd, int options);
 #define F_SETFL   4
-#define O_NDELAY  04000
+#define O_NONBLOCK  04000
 
 /* we are providing a real h_errno variable */
 #undef h_errno
diff --git a/nt/inc/unistd.h b/nt/inc/unistd.h
index b0f3092cafb..0173fdbb943 100644
--- a/nt/inc/unistd.h
+++ b/nt/inc/unistd.h
@@ -26,4 +26,17 @@ extern int faccessat (int, char const *, int, int);
 #define AT_EACCESS 4
 #define AT_SYMLINK_NOFOLLOW 4096
 
+/* Here are some more fcntl.h macros that default to gnulib-compatible
+   values.  Include <fcntl.h> first, to make sure we don't override
+   its values if any.  FIXME: If we know <fcntl.h> does not define
+   O_NOCTTY and O_RDWR, this can be replaced with a simple "#define
+   O_NOCTTY 0" and "#define O_RDWR 2".  */
+#include <fcntl.h>
+#ifndef O_NOCTTY
+#define O_NOCTTY 0
+#endif
+#ifndef O_RDWR
+#define O_RDWR 2
+#endif
+
 #endif  /* _UNISTD_H */
diff --git a/src/ChangeLog b/src/ChangeLog
index df8bf602afe..a847a3913dd 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,30 @@
+2012-11-17  Paul Eggert  <eggert@cs.ucla.edu>
+
+        Assume POSIX 1003.1-1988 or later for fcntl.h (Bug#12881).
+        * callproc.c (relocate_fd): Assume F_DUPFD.
+        * emacs.c, term.c (O_RDWR): Remove.
+        * keyboard.c (tty_read_avail_input): Use O_NONBLOCK rather than
+        O_NDELAY, since O_NONBLOCK is the standard name for this flag.
+        * nsterm.m: Assume <fcntl.h> exists.
+        * process.c (NON_BLOCKING_CONNECT, allocate_pty, create_process)
+        (create_pty, Fmake_network_process, server_accept_connection)
+        (wait_reading_process_output, init_process_emacs):
+        Assume O_NONBLOCK.
+        (wait_reading_process_output): Put in a special case for WINDOWSNT
+        to mimick the older behavior where it had O_NDELAY but not O_NONBLOCK.
+        It's not clear this is needed, but it's a more-conservative change.
+        (create_process): Assume FD_CLOEXEC.
+        (create_process, create_pty): Assume O_NOCTTY.
+        * sysdep.c (init_sys_modes, reset_sys_modes): Assume F_SETFL.
+        (reset_sys_modes): Use O_NONBLOCK rather than O_NDELAY.
+        Omit if not DOS_NT, since F_GETFL is not defined there.
+        (serial_open): Assume O_NONBLOCK and O_NOCTTY.
+        * term.c: Include <fcntl.h>, for flags like O_NOCTTY.
+        (O_NOCTTY): Remove.
+        (init_tty): Assume O_IGNORE_CTTY is defined to 0 on platforms that
+        lack it, since gnulib guarantees this.
+        * w32.c (fcntl): Test for O_NONBLOCK rather than O_NDELAY.
+
 2012-11-17  Eli Zaretskii  <eliz@gnu.org>
 
         * w32.c (faccessat): Pretend that directories have the execute bit
diff --git a/src/callproc.c b/src/callproc.c
index 8ecaba2b408..c9a504746b3 100644
--- a/src/callproc.c
+++ b/src/callproc.c
@@ -1317,16 +1317,7 @@ relocate_fd (int fd, int minfd)
     return fd;
   else
     {
-      int new;
-#ifdef F_DUPFD
-      new = fcntl (fd, F_DUPFD, minfd);
-#else
-      new = dup (fd);
-      if (new != -1)
-        /* Note that we hold the original FD open while we recurse,
-           to guarantee we'll get a new FD if we need it.  */
-        new = relocate_fd (new, minfd);
-#endif
+      int new = fcntl (fd, F_DUPFD, minfd);
       if (new == -1)
         {
           const char *message_1 = "Error while setting up child: ";
diff --git a/src/emacs.c b/src/emacs.c
index fee9c332c55..d69dbfda7bf 100644
--- a/src/emacs.c
+++ b/src/emacs.c
@@ -95,10 +95,6 @@ extern void moncontrol (int mode);
 #include <sys/personality.h>
 #endif
 
-#ifndef O_RDWR
-#define O_RDWR 2
-#endif
-
 static const char emacs_version[] = VERSION;
 static const char emacs_copyright[] = COPYRIGHT;
 
diff --git a/src/keyboard.c b/src/keyboard.c
index 8f3a206139d..951d4ad79dc 100644
--- a/src/keyboard.c
+++ b/src/keyboard.c
@@ -6948,7 +6948,7 @@ tty_read_avail_input (struct terminal *terminal,
 #elif defined USG || defined CYGWIN
   /* Read some input if available, but don't wait.  */
   n_to_read = sizeof cbuf;
-  fcntl (fileno (tty->input), F_SETFL, O_NDELAY);
+  fcntl (fileno (tty->input), F_SETFL, O_NONBLOCK);
 #else
 # error "Cannot read without possibly delaying"
 #endif
@@ -6982,7 +6982,7 @@ tty_read_avail_input (struct terminal *terminal,
     }
   while (
          /* We used to retry the read if it was interrupted.
-            But this does the wrong thing when O_NDELAY causes
+            But this does the wrong thing when O_NONBLOCK causes
             an EAGAIN error.  Does anybody know of a situation
             where a retry is actually needed?  */
 #if 0
diff --git a/src/nsterm.m b/src/nsterm.m
index 3640ac0c5e8..8773c6faf9f 100644
--- a/src/nsterm.m
+++ b/src/nsterm.m
@@ -30,6 +30,7 @@ GNUstep port and post-20 update by Adrian Robert (arobert@cogsci.ucsd.edu)
    interpretation of even the system includes. */
 #include <config.h>
 
+#include <fcntl.h>
 #include <math.h>
 #include <pthread.h>
 #include <sys/types.h>
@@ -41,10 +42,6 @@ GNUstep port and post-20 update by Adrian Robert (arobert@cogsci.ucsd.edu)
 #include <c-strcase.h>
 #include <ftoastr.h>
 
-#ifdef HAVE_FCNTL_H
-#include <fcntl.h>
-#endif
-
 #include "lisp.h"
 #include "blockinput.h"
 #include "sysselect.h"
diff --git a/src/process.c b/src/process.c
index 51648187aff..0036ce595f5 100644
--- a/src/process.c
+++ b/src/process.c
@@ -196,11 +196,9 @@ static EMACS_INT update_tick;
 #ifndef NON_BLOCKING_CONNECT
 #ifdef HAVE_SELECT
 #if defined (HAVE_GETPEERNAME) || defined (GNU_LINUX)
-#if O_NONBLOCK || O_NDELAY
 #if defined (EWOULDBLOCK) || defined (EINPROGRESS)
 #define NON_BLOCKING_CONNECT
 #endif /* EWOULDBLOCK || EINPROGRESS */
-#endif /* O_NONBLOCK || O_NDELAY */
 #endif /* HAVE_GETPEERNAME || GNU_LINUX */
 #endif /* HAVE_SELECT */
 #endif /* NON_BLOCKING_CONNECT */
@@ -639,13 +637,7 @@ allocate_pty (void)
 #ifdef PTY_OPEN
         PTY_OPEN;
 #else /* no PTY_OPEN */
-        {
-#  if O_NONBLOCK
-          fd = emacs_open (pty_name, O_RDWR | O_NONBLOCK, 0);
-#  else
-          fd = emacs_open (pty_name, O_RDWR | O_NDELAY, 0);
-#  endif
-        }
+        fd = emacs_open (pty_name, O_RDWR | O_NONBLOCK, 0);
 #endif /* no PTY_OPEN */
 
         if (fd >= 0)
@@ -1583,7 +1575,7 @@ create_process (Lisp_Object process, char **new_argv, Lisp_Object current_dir)
   int inchannel, outchannel;
   pid_t pid;
   int sv[2];
-#if !defined (WINDOWSNT) && defined (FD_CLOEXEC)
+#ifndef WINDOWSNT
   int wait_child_setup[2];
 #endif
 #ifdef SIGCHLD
@@ -1609,13 +1601,9 @@ create_process (Lisp_Object process, char **new_argv, Lisp_Object current_dir)
 #if ! defined (USG) || defined (USG_SUBTTY_WORKS)
       /* On most USG systems it does not work to open the pty's tty here,
          then close it and reopen it in the child.  */
-#if O_NOCTTY
       /* Don't let this terminal become our controlling terminal
          (in case we don't have one).  */
       forkout = forkin = emacs_open (pty_name, O_RDWR | O_NOCTTY, 0);
-#else
-      forkout = forkin = emacs_open (pty_name, O_RDWR, 0);
-#endif
       if (forkin < 0)
         report_file_error ("Opening pty", Qnil);
 #else
@@ -1644,7 +1632,7 @@ create_process (Lisp_Object process, char **new_argv, Lisp_Object current_dir)
       forkin = sv[0];
     }
 
-#if !defined (WINDOWSNT) && defined (FD_CLOEXEC)
+#ifndef WINDOWSNT
     {
       int tem;
 
@@ -1663,15 +1651,8 @@ create_process (Lisp_Object process, char **new_argv, Lisp_Object current_dir)
     }
 #endif
 
-#if O_NONBLOCK
   fcntl (inchannel, F_SETFL, O_NONBLOCK);
   fcntl (outchannel, F_SETFL, O_NONBLOCK);
-#else
-#if O_NDELAY
-  fcntl (inchannel, F_SETFL, O_NDELAY);
-  fcntl (outchannel, F_SETFL, O_NDELAY);
-#endif
-#endif
 
   /* Record this as an active process, with its channels.
      As a result, child_setup will close Emacs's side of the pipes.  */
@@ -1830,9 +1811,7 @@ create_process (Lisp_Object process, char **new_argv, Lisp_Object current_dir)
       pid = child_setup (xforkin, xforkout, xforkout,
                          new_argv, 1, encoded_current_dir);
 #else  /* not WINDOWSNT */
-#ifdef FD_CLOEXEC
       emacs_close (wait_child_setup[0]);
-#endif
       child_setup (xforkin, xforkout, xforkout,
                    new_argv, 1, encoded_current_dir);
 #endif /* not WINDOWSNT */
@@ -1891,7 +1870,7 @@ create_process (Lisp_Object process, char **new_argv, Lisp_Object current_dir)
 
       pset_tty_name (XPROCESS (process), lisp_pty_name);
 
-#if !defined (WINDOWSNT) && defined (FD_CLOEXEC)
+#ifndef WINDOWSNT
       /* Wait for child_setup to complete in case that vfork is
          actually defined as fork.  The descriptor wait_child_setup[1]
          of a pipe is closed at the child side either by close-on-exec
@@ -1928,13 +1907,9 @@ create_pty (Lisp_Object process)
 #if ! defined (USG) || defined (USG_SUBTTY_WORKS)
       /* On most USG systems it does not work to open the pty's tty here,
          then close it and reopen it in the child.  */
-#if O_NOCTTY
       /* Don't let this terminal become our controlling terminal
          (in case we don't have one).  */
       int forkout = emacs_open (pty_name, O_RDWR | O_NOCTTY, 0);
-#else
-      int forkout = emacs_open (pty_name, O_RDWR, 0);
-#endif
       if (forkout < 0)
         report_file_error ("Opening pty", Qnil);
 #if defined (DONT_REOPEN_PTY)
@@ -1948,15 +1923,8 @@ create_pty (Lisp_Object process)
     }
 #endif /* HAVE_PTYS */
 
-#if O_NONBLOCK
   fcntl (inchannel, F_SETFL, O_NONBLOCK);
   fcntl (outchannel, F_SETFL, O_NONBLOCK);
-#else
-#if O_NDELAY
-  fcntl (inchannel, F_SETFL, O_NDELAY);
-  fcntl (outchannel, F_SETFL, O_NDELAY);
-#endif
-#endif
 
   /* Record this as an active process, with its channels.
      As a result, child_setup will close Emacs's side of the pipes.  */
@@ -2912,13 +2880,9 @@ usage: (make-network-process &rest ARGS)  */)
     {
       /* Don't support network sockets when non-blocking mode is
          not available, since a blocked Emacs is not useful.  */
-#if !O_NONBLOCK && !O_NDELAY
-      error ("Network servers not supported");
-#else
       is_server = 1;
       if (TYPE_RANGED_INTEGERP (int, tem))
         backlog = XINT (tem);
-#endif
     }
 
   /* Make QCaddress an alias for :local (server) or :remote (client).  */
@@ -3178,11 +3142,7 @@ usage: (make-network-process &rest ARGS)  */)
 #ifdef NON_BLOCKING_CONNECT
       if (is_non_blocking_client)
         {
-#if O_NONBLOCK
           ret = fcntl (s, F_SETFL, O_NONBLOCK);
-#else
-          ret = fcntl (s, F_SETFL, O_NDELAY);
-#endif
           if (ret < 0)
             {
               xerrno = errno;
@@ -3395,13 +3355,7 @@ usage: (make-network-process &rest ARGS)  */)
 
   chan_process[inch] = proc;
 
-#if O_NONBLOCK
   fcntl (inch, F_SETFL, O_NONBLOCK);
-#else
-#if O_NDELAY
-  fcntl (inch, F_SETFL, O_NDELAY);
-#endif
-#endif
 
   p = XPROCESS (proc);
 
@@ -4130,13 +4084,7 @@ server_accept_connection (Lisp_Object server, int channel)
 
   chan_process[s] = proc;
 
-#if O_NONBLOCK
   fcntl (s, F_SETFL, O_NONBLOCK);
-#else
-#if O_NDELAY
-  fcntl (s, F_SETFL, O_NDELAY);
-#endif
-#endif
 
   p = XPROCESS (proc);
 
@@ -4832,23 +4780,17 @@ wait_reading_process_output (intmax_t time_limit, int nsecs, int read_kbd,
               else if (nread == -1 && errno == EWOULDBLOCK)
                 ;
 #endif
-              /* ISC 4.1 defines both EWOULDBLOCK and O_NONBLOCK,
-                 and Emacs uses O_NONBLOCK, so what we get is EAGAIN.  */
-#if O_NONBLOCK
-              else if (nread == -1 && errno == EAGAIN)
-                ;
-#else
-#if O_NDELAY
               else if (nread == -1 && errno == EAGAIN)
                 ;
+#ifdef WINDOWSNT
+              /* FIXME: Is this special case still needed?  */
               /* Note that we cannot distinguish between no input
                  available now and a closed pipe.
                  With luck, a closed pipe will be accompanied by
                  subprocess termination and SIGCHLD.  */
               else if (nread == 0 && !NETCONN_P (proc) && !SERIALCONN_P (proc))
                 ;
-#endif /* O_NDELAY */
-#endif /* O_NONBLOCK */
+#endif
 #ifdef HAVE_PTYS
               /* On some OSs with ptys, when the process on one end of
                  a pty exits, the other end gets an error reading with
@@ -7312,9 +7254,7 @@ init_process_emacs (void)
 #ifdef HAVE_GETSOCKNAME
    ADD_SUBFEATURE (QCservice, Qt);
 #endif
-#if O_NONBLOCK || O_NDELAY
    ADD_SUBFEATURE (QCserver, Qt);
-#endif
 
    for (sopt = socket_options; sopt->name; sopt++)
      subfeatures = pure_cons (intern_c_string (sopt->name), subfeatures);
diff --git a/src/sysdep.c b/src/sysdep.c
index 06dc41b511e..7c5c144fa8c 100644
--- a/src/sysdep.c
+++ b/src/sysdep.c
@@ -1036,8 +1036,7 @@ init_sys_modes (struct tty_display_info *tty_out)
 #endif
 #endif
 
-#ifdef F_SETFL
-#ifdef F_GETOWN         /* F_SETFL does not imply existence of F_GETOWN */
+#ifdef F_GETOWN
   if (interrupt_input)
     {
       old_fcntl_owner[fileno (tty_out->input)] =
@@ -1055,7 +1054,6 @@ init_sys_modes (struct tty_display_info *tty_out)
 #endif /* HAVE_GPM */
     }
 #endif /* F_GETOWN */
-#endif /* F_SETFL */
 
 #ifdef _IOFBF
   /* This symbol is defined on recent USG systems.
@@ -1275,8 +1273,8 @@ reset_sys_modes (struct tty_display_info *tty_out)
   fsync (fileno (tty_out->output));
 #endif
 
-#ifdef F_SETFL
-#ifdef F_SETOWN         /* F_SETFL does not imply existence of F_SETOWN */
+#ifndef DOS_NT
+#ifdef F_SETOWN
   if (interrupt_input)
     {
       reset_sigio (fileno (tty_out->input));
@@ -1284,11 +1282,9 @@ reset_sys_modes (struct tty_display_info *tty_out)
              old_fcntl_owner[fileno (tty_out->input)]);
     }
 #endif /* F_SETOWN */
-#if O_NDELAY
   fcntl (fileno (tty_out->input), F_SETFL,
-         fcntl (fileno (tty_out->input), F_GETFL, 0) & ~O_NDELAY);
+         fcntl (fileno (tty_out->input), F_GETFL, 0) & ~O_NONBLOCK);
 #endif
-#endif /* F_SETFL */
 
   if (tty_out->old_tty)
     while (emacs_set_tty (fileno (tty_out->input),
@@ -2377,19 +2373,7 @@ safe_strsignal (int code)
 int
 serial_open (char *port)
 {
-  int fd = -1;
-
-  fd = emacs_open ((char*) port,
-                   O_RDWR
-#if O_NONBLOCK
-                   | O_NONBLOCK
-#else
-                   | O_NDELAY
-#endif
-#if O_NOCTTY
-                   | O_NOCTTY
-#endif
-                   , 0);
+  int fd = emacs_open (port, O_RDWR | O_NOCTTY | O_NONBLOCK, 0);
   if (fd < 0)
     {
       error ("Could not open %s: %s",
diff --git a/src/term.c b/src/term.c
index 96549290da5..481a3423989 100644
--- a/src/term.c
+++ b/src/term.c
@@ -20,8 +20,9 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 /* New redisplay, TTY faces by Gerd Moellmann <gerd@gnu.org>.  */
 
 #include <config.h>
-#include <stdio.h>
 #include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
 #include <sys/file.h>
 #include <sys/time.h>
 #include <unistd.h>
@@ -55,14 +56,6 @@ static int been_here = -1;
 #include "xterm.h"
 #endif
 
-#ifndef O_RDWR
-#define O_RDWR 2
-#endif
-
-#ifndef O_NOCTTY
-#define O_NOCTTY 0
-#endif
-
 /* The name of the default console device.  */
 #ifdef WINDOWSNT
 #define DEV_TTY  "CONOUT$"
@@ -2989,22 +2982,18 @@ init_tty (const char *name, const char *terminal_type, int must_succeed)
   set_tty_hooks (terminal);
 
   {
-    int fd;
+    /* Open the terminal device.  */
     FILE *file;
 
-#if O_IGNORE_CTTY
-    if (!ctty)
-      /* Open the terminal device.  Don't recognize it as our
-         controlling terminal, and don't make it the controlling tty
-         if we don't have one at the moment.  */
-      fd = emacs_open (name, O_RDWR | O_IGNORE_CTTY | O_NOCTTY, 0);
-    else
-#endif /* O_IGNORE_CTTY */
-      /* Alas, O_IGNORE_CTTY is a GNU extension that seems to be only
-         defined on Hurd.  On other systems, we need to explicitly
-         dissociate ourselves from the controlling tty when we want to
-         open a frame on the same terminal.  */
-      fd = emacs_open (name, O_RDWR | O_NOCTTY, 0);
+    /* If !ctty, don't recognize it as our controlling terminal, and
+       don't make it the controlling tty if we don't have one now.
+
+       Alas, O_IGNORE_CTTY is a GNU extension that seems to be only
+       defined on Hurd.  On other systems, we need to explicitly
+       dissociate ourselves from the controlling tty when we want to
+       open a frame on the same terminal.  */
+    int flags = O_RDWR | O_NOCTTY | (ctty ? 0 : O_IGNORE_CTTY);
+    int fd = emacs_open (name, flags, 0);
 
     tty->name = xstrdup (name);
     terminal->name = xstrdup (name);
@@ -3023,10 +3012,8 @@ init_tty (const char *name, const char *terminal_type, int must_succeed)
                      name);
       }
 
-#if !O_IGNORE_CTTY
-    if (!ctty)
+    if (!O_IGNORE_CTTY && !ctty)
       dissociate_if_controlling_tty (fd);
-#endif
 
     file = fdopen (fd, "w+");
     tty->input = file;
diff --git a/src/w32.c b/src/w32.c
index 46433626802..94cf472a4ae 100644
--- a/src/w32.c
+++ b/src/w32.c
@@ -5854,7 +5854,7 @@ fcntl (int s, int cmd, int options)
   check_errno ();
   if (fd_info[s].flags & FILE_SOCKET)
     {
-      if (cmd == F_SETFL && options == O_NDELAY)
+      if (cmd == F_SETFL && options == O_NONBLOCK)
         {
           unsigned long nblock = 1;
           int rc = pfn_ioctlsocket (SOCK_HANDLE (s), FIONBIO, &nblock);