diff --git a/Include/pyport.h b/Include/pyport.h
index bafa0c8..ce760d2 100644
--- a/Include/pyport.h
+++ b/Include/pyport.h
@@ -122,6 +122,10 @@
 /* Smallest negative value of type Py_ssize_t. */
 #define PY_SSIZE_T_MIN (-PY_SSIZE_T_MAX-1)
 
+#if SIZEOF_PID_T > SIZEOF_LONG
+#   error "Python doesn't support sizeof(pid_t) > sizeof(long)"
+#endif
+
 /* PY_FORMAT_SIZE_T is a platform-specific modifier for use in a printf
  * format to convert an argument with the width of a size_t or Py_ssize_t.
  * C99 introduced "z" for this purpose, but not all platforms support that;
@@ -573,7 +577,7 @@
    functions, even though they are included in libutil. */
 #include <termios.h>
 extern int openpty(int *, int *, char *, struct termios *, struct winsize *);
-extern int forkpty(int *, char *, struct termios *, struct winsize *);
+extern pid_t forkpty(int *, char *, struct termios *, struct winsize *);
 #endif /* !defined(HAVE_PTY_H) && !defined(HAVE_LIBUTIL_H) */
 #endif /* defined(HAVE_OPENPTY) || defined(HAVE_FORKPTY) */
 
diff --git a/Misc/NEWS b/Misc/NEWS
index 45b266c..4a74446 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -12,6 +12,9 @@
 Core and builtins
 -----------------
 
+- Bug #1983: Fixed return type of fork(), fork1() and forkpty() calls.
+  Python expected the return type int but the fork familie returns pi_t.
+
 - Issue #1678380: Fix a bug that identifies 0j and -0j when they appear
   in the same code unit.
 
@@ -1386,6 +1389,9 @@
 Build
 -----
 
+- Bug #1983: Added a check to pyport to verify that sizeof(pid_t) is
+  smaller or equal sizeof(long).
+
 - Bug #1234: Fixed semaphore errors on AIX 5.2
 
 - Issue #1726: Remove Python/atof.c from PCBuild/pythoncore.vcproj
diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c
index 0038703..8663c99 100644
--- a/Modules/posixmodule.c
+++ b/Modules/posixmodule.c
@@ -3575,11 +3575,11 @@
 static PyObject *
 posix_fork1(PyObject *self, PyObject *noargs)
 {
-	int pid = fork1();
+	pid_t pid = fork1();
 	if (pid == -1)
 		return posix_error();
 	PyOS_AfterFork();
-	return PyInt_FromLong((long)pid);
+	return PyInt_FromLong(pid);
 }
 #endif
 
@@ -3593,12 +3593,12 @@
 static PyObject *
 posix_fork(PyObject *self, PyObject *noargs)
 {
-	int pid = fork();
+	pid_t pid = fork();
 	if (pid == -1)
 		return posix_error();
 	if (pid == 0)
 		PyOS_AfterFork();
-	return PyInt_FromLong((long)pid);
+	return PyInt_FromLong(pid);
 }
 #endif
 
@@ -3700,14 +3700,15 @@
 static PyObject *
 posix_forkpty(PyObject *self, PyObject *noargs)
 {
-	int master_fd = -1, pid;
+	int master_fd = -1;
+	pid_t pid;
 
 	pid = forkpty(&master_fd, NULL, NULL, NULL);
 	if (pid == -1)
 		return posix_error();
 	if (pid == 0)
 		PyOS_AfterFork();
-	return Py_BuildValue("(ii)", pid, master_fd);
+	return Py_BuildValue("(li)", pid, master_fd);
 }
 #endif
 
diff --git a/configure b/configure
index 1a7dfc4..85359af 100755
--- a/configure
+++ b/configure
@@ -1,5 +1,5 @@
 #! /bin/sh
-# From configure.in Revision: 60141 .
+# From configure.in Revision: 60464 .
 # Guess values for system-dependent variables and create Makefiles.
 # Generated by GNU Autoconf 2.61 for python 2.6.
 #
@@ -10160,6 +10160,411 @@
 _ACEOF
 
 
+{ echo "$as_me:$LINENO: checking for pid_t" >&5
+echo $ECHO_N "checking for pid_t... $ECHO_C" >&6; }
+if test "${ac_cv_type_pid_t+set}" = set; then
+  echo $ECHO_N "(cached) $ECHO_C" >&6
+else
+  cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+$ac_includes_default
+typedef pid_t ac__type_new_;
+int
+main ()
+{
+if ((ac__type_new_ *) 0)
+  return 0;
+if (sizeof (ac__type_new_))
+  return 0;
+  ;
+  return 0;
+}
+_ACEOF
+rm -f conftest.$ac_objext
+if { (ac_try="$ac_compile"
+case "(($ac_try" in
+  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+  *) ac_try_echo=$ac_try;;
+esac
+eval "echo \"\$as_me:$LINENO: $ac_try_echo\"") >&5
+  (eval "$ac_compile") 2>conftest.er1
+  ac_status=$?
+  grep -v '^ *+' conftest.er1 >conftest.err
+  rm -f conftest.er1
+  cat conftest.err >&5
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } && {
+	 test -z "$ac_c_werror_flag" ||
+	 test ! -s conftest.err
+       } && test -s conftest.$ac_objext; then
+  ac_cv_type_pid_t=yes
+else
+  echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+	ac_cv_type_pid_t=no
+fi
+
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ echo "$as_me:$LINENO: result: $ac_cv_type_pid_t" >&5
+echo "${ECHO_T}$ac_cv_type_pid_t" >&6; }
+
+# The cast to long int works around a bug in the HP C Compiler
+# version HP92453-01 B.11.11.23709.GP, which incorrectly rejects
+# declarations like `int a3[[(sizeof (unsigned char)) >= 0]];'.
+# This bug is HP SR number 8606223364.
+{ echo "$as_me:$LINENO: checking size of pid_t" >&5
+echo $ECHO_N "checking size of pid_t... $ECHO_C" >&6; }
+if test "${ac_cv_sizeof_pid_t+set}" = set; then
+  echo $ECHO_N "(cached) $ECHO_C" >&6
+else
+  if test "$cross_compiling" = yes; then
+  # Depending upon the size, compute the lo and hi bounds.
+cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+$ac_includes_default
+   typedef pid_t ac__type_sizeof_;
+int
+main ()
+{
+static int test_array [1 - 2 * !(((long int) (sizeof (ac__type_sizeof_))) >= 0)];
+test_array [0] = 0
+
+  ;
+  return 0;
+}
+_ACEOF
+rm -f conftest.$ac_objext
+if { (ac_try="$ac_compile"
+case "(($ac_try" in
+  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+  *) ac_try_echo=$ac_try;;
+esac
+eval "echo \"\$as_me:$LINENO: $ac_try_echo\"") >&5
+  (eval "$ac_compile") 2>conftest.er1
+  ac_status=$?
+  grep -v '^ *+' conftest.er1 >conftest.err
+  rm -f conftest.er1
+  cat conftest.err >&5
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } && {
+	 test -z "$ac_c_werror_flag" ||
+	 test ! -s conftest.err
+       } && test -s conftest.$ac_objext; then
+  ac_lo=0 ac_mid=0
+  while :; do
+    cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+$ac_includes_default
+   typedef pid_t ac__type_sizeof_;
+int
+main ()
+{
+static int test_array [1 - 2 * !(((long int) (sizeof (ac__type_sizeof_))) <= $ac_mid)];
+test_array [0] = 0
+
+  ;
+  return 0;
+}
+_ACEOF
+rm -f conftest.$ac_objext
+if { (ac_try="$ac_compile"
+case "(($ac_try" in
+  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+  *) ac_try_echo=$ac_try;;
+esac
+eval "echo \"\$as_me:$LINENO: $ac_try_echo\"") >&5
+  (eval "$ac_compile") 2>conftest.er1
+  ac_status=$?
+  grep -v '^ *+' conftest.er1 >conftest.err
+  rm -f conftest.er1
+  cat conftest.err >&5
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } && {
+	 test -z "$ac_c_werror_flag" ||
+	 test ! -s conftest.err
+       } && test -s conftest.$ac_objext; then
+  ac_hi=$ac_mid; break
+else
+  echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+	ac_lo=`expr $ac_mid + 1`
+			if test $ac_lo -le $ac_mid; then
+			  ac_lo= ac_hi=
+			  break
+			fi
+			ac_mid=`expr 2 '*' $ac_mid + 1`
+fi
+
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+  done
+else
+  echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+	cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+$ac_includes_default
+   typedef pid_t ac__type_sizeof_;
+int
+main ()
+{
+static int test_array [1 - 2 * !(((long int) (sizeof (ac__type_sizeof_))) < 0)];
+test_array [0] = 0
+
+  ;
+  return 0;
+}
+_ACEOF
+rm -f conftest.$ac_objext
+if { (ac_try="$ac_compile"
+case "(($ac_try" in
+  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+  *) ac_try_echo=$ac_try;;
+esac
+eval "echo \"\$as_me:$LINENO: $ac_try_echo\"") >&5
+  (eval "$ac_compile") 2>conftest.er1
+  ac_status=$?
+  grep -v '^ *+' conftest.er1 >conftest.err
+  rm -f conftest.er1
+  cat conftest.err >&5
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } && {
+	 test -z "$ac_c_werror_flag" ||
+	 test ! -s conftest.err
+       } && test -s conftest.$ac_objext; then
+  ac_hi=-1 ac_mid=-1
+  while :; do
+    cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+$ac_includes_default
+   typedef pid_t ac__type_sizeof_;
+int
+main ()
+{
+static int test_array [1 - 2 * !(((long int) (sizeof (ac__type_sizeof_))) >= $ac_mid)];
+test_array [0] = 0
+
+  ;
+  return 0;
+}
+_ACEOF
+rm -f conftest.$ac_objext
+if { (ac_try="$ac_compile"
+case "(($ac_try" in
+  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+  *) ac_try_echo=$ac_try;;
+esac
+eval "echo \"\$as_me:$LINENO: $ac_try_echo\"") >&5
+  (eval "$ac_compile") 2>conftest.er1
+  ac_status=$?
+  grep -v '^ *+' conftest.er1 >conftest.err
+  rm -f conftest.er1
+  cat conftest.err >&5
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } && {
+	 test -z "$ac_c_werror_flag" ||
+	 test ! -s conftest.err
+       } && test -s conftest.$ac_objext; then
+  ac_lo=$ac_mid; break
+else
+  echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+	ac_hi=`expr '(' $ac_mid ')' - 1`
+			if test $ac_mid -le $ac_hi; then
+			  ac_lo= ac_hi=
+			  break
+			fi
+			ac_mid=`expr 2 '*' $ac_mid`
+fi
+
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+  done
+else
+  echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+	ac_lo= ac_hi=
+fi
+
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+# Binary search between lo and hi bounds.
+while test "x$ac_lo" != "x$ac_hi"; do
+  ac_mid=`expr '(' $ac_hi - $ac_lo ')' / 2 + $ac_lo`
+  cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+$ac_includes_default
+   typedef pid_t ac__type_sizeof_;
+int
+main ()
+{
+static int test_array [1 - 2 * !(((long int) (sizeof (ac__type_sizeof_))) <= $ac_mid)];
+test_array [0] = 0
+
+  ;
+  return 0;
+}
+_ACEOF
+rm -f conftest.$ac_objext
+if { (ac_try="$ac_compile"
+case "(($ac_try" in
+  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+  *) ac_try_echo=$ac_try;;
+esac
+eval "echo \"\$as_me:$LINENO: $ac_try_echo\"") >&5
+  (eval "$ac_compile") 2>conftest.er1
+  ac_status=$?
+  grep -v '^ *+' conftest.er1 >conftest.err
+  rm -f conftest.er1
+  cat conftest.err >&5
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } && {
+	 test -z "$ac_c_werror_flag" ||
+	 test ! -s conftest.err
+       } && test -s conftest.$ac_objext; then
+  ac_hi=$ac_mid
+else
+  echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+	ac_lo=`expr '(' $ac_mid ')' + 1`
+fi
+
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+done
+case $ac_lo in
+?*) ac_cv_sizeof_pid_t=$ac_lo;;
+'') if test "$ac_cv_type_pid_t" = yes; then
+     { { echo "$as_me:$LINENO: error: cannot compute sizeof (pid_t)
+See \`config.log' for more details." >&5
+echo "$as_me: error: cannot compute sizeof (pid_t)
+See \`config.log' for more details." >&2;}
+   { (exit 77); exit 77; }; }
+   else
+     ac_cv_sizeof_pid_t=0
+   fi ;;
+esac
+else
+  cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+$ac_includes_default
+   typedef pid_t ac__type_sizeof_;
+static long int longval () { return (long int) (sizeof (ac__type_sizeof_)); }
+static unsigned long int ulongval () { return (long int) (sizeof (ac__type_sizeof_)); }
+#include <stdio.h>
+#include <stdlib.h>
+int
+main ()
+{
+
+  FILE *f = fopen ("conftest.val", "w");
+  if (! f)
+    return 1;
+  if (((long int) (sizeof (ac__type_sizeof_))) < 0)
+    {
+      long int i = longval ();
+      if (i != ((long int) (sizeof (ac__type_sizeof_))))
+	return 1;
+      fprintf (f, "%ld\n", i);
+    }
+  else
+    {
+      unsigned long int i = ulongval ();
+      if (i != ((long int) (sizeof (ac__type_sizeof_))))
+	return 1;
+      fprintf (f, "%lu\n", i);
+    }
+  return ferror (f) || fclose (f) != 0;
+
+  ;
+  return 0;
+}
+_ACEOF
+rm -f conftest$ac_exeext
+if { (ac_try="$ac_link"
+case "(($ac_try" in
+  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+  *) ac_try_echo=$ac_try;;
+esac
+eval "echo \"\$as_me:$LINENO: $ac_try_echo\"") >&5
+  (eval "$ac_link") 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } && { ac_try='./conftest$ac_exeext'
+  { (case "(($ac_try" in
+  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+  *) ac_try_echo=$ac_try;;
+esac
+eval "echo \"\$as_me:$LINENO: $ac_try_echo\"") >&5
+  (eval "$ac_try") 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }; then
+  ac_cv_sizeof_pid_t=`cat conftest.val`
+else
+  echo "$as_me: program exited with status $ac_status" >&5
+echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+( exit $ac_status )
+if test "$ac_cv_type_pid_t" = yes; then
+     { { echo "$as_me:$LINENO: error: cannot compute sizeof (pid_t)
+See \`config.log' for more details." >&5
+echo "$as_me: error: cannot compute sizeof (pid_t)
+See \`config.log' for more details." >&2;}
+   { (exit 77); exit 77; }; }
+   else
+     ac_cv_sizeof_pid_t=0
+   fi
+fi
+rm -f core *.core core.conftest.* gmon.out bb.out conftest$ac_exeext conftest.$ac_objext conftest.$ac_ext
+fi
+rm -f conftest.val
+fi
+{ echo "$as_me:$LINENO: result: $ac_cv_sizeof_pid_t" >&5
+echo "${ECHO_T}$ac_cv_sizeof_pid_t" >&6; }
+
+
+
+cat >>confdefs.h <<_ACEOF
+#define SIZEOF_PID_T $ac_cv_sizeof_pid_t
+_ACEOF
+
+
 
 { echo "$as_me:$LINENO: checking for long long support" >&5
 echo $ECHO_N "checking for long long support... $ECHO_C" >&6; }
diff --git a/configure.in b/configure.in
index 2ee4744..1e83bd0 100644
--- a/configure.in
+++ b/configure.in
@@ -1202,7 +1202,7 @@
 AC_TYPE_SIGNAL
 AC_TYPE_SIZE_T
 AC_TYPE_UID_T
-AC_CHECK_TYPE(ssize_t, 
+AC_CHECK_TYPE(ssize_t,
   AC_DEFINE(HAVE_SSIZE_T, 1, Define if your compiler provides ssize_t),,)
 
 # Sizes of various common basic types
@@ -1215,6 +1215,7 @@
 AC_CHECK_SIZEOF(double, 8)
 AC_CHECK_SIZEOF(fpos_t, 4)
 AC_CHECK_SIZEOF(size_t, 4)
+AC_CHECK_SIZEOF(pid_t, 4)
 
 AC_MSG_CHECKING(for long long support)
 have_long_long=no
diff --git a/pyconfig.h.in b/pyconfig.h.in
index ad89148..35a873a 100644
--- a/pyconfig.h.in
+++ b/pyconfig.h.in
@@ -869,6 +869,9 @@
 /* The number of bytes in an off_t. */
 #undef SIZEOF_OFF_T
 
+/* The size of `pid_t', as computed by sizeof. */
+#undef SIZEOF_PID_T
+
 /* The number of bytes in a pthread_t. */
 #undef SIZEOF_PTHREAD_T