Add support to port/snprintf.c for position parameter specification:

+ # Determine if printf supports %1$ argument selection, e.g. %5$ selects
+ # the fifth argument after the printf print string.
+ # This is not in the C99 standard, but in the Single Unix Specification (SUS).
+ # It is used in our langauge translation strings.

Nicolai Tufar with configure changes by Bruce.

configure

@@ -12162,6 +12162,63 @@ fi
 done
 
 
+echo "$as_me:$LINENO: checking printf supports argument control" >&5
+echo $ECHO_N "checking printf supports argument control... $ECHO_C" >&6
+if test "${pgac_cv_printf_arg_control+set}" = set; then
+  echo $ECHO_N "(cached) $ECHO_C" >&6
+else
+  if test "$cross_compiling" = yes; then
+  pgac_cv_printf_arg_control=cross
+else
+  cat >conftest.$ac_ext <<_ACEOF
+#line $LINENO "configure"
+#include "confdefs.h"
+#include <stdio.h>
+
+int does_printf_have_arg_control()
+{
+  char buf[100];
+
+  /* can it swap arguments? */
+  snprintf(buf, 100, "%2$d|%1$d", 3, 4);
+  if (strcmp(buf, "4|3") != 0)
+    return 0;
+  return 1;
+}
+main() {
+  exit(! does_printf_have_arg_control());
+}
+_ACEOF
+rm -f conftest$ac_exeext
+if { (eval echo "$as_me:$LINENO: \"$ac_link\"") >&5
+  (eval $ac_link) 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } && { ac_try='./conftest$ac_exeext'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }; then
+  pgac_cv_printf_arg_control=yes
+else
+  echo "$as_me: program exited with status $ac_status" >&5
+echo "$as_me: failed program was:" >&5
+cat conftest.$ac_ext >&5
+( exit $ac_status )
+pgac_cv_printf_arg_control=no
+fi
+rm -f core core.* *.core conftest$ac_exeext conftest.$ac_objext conftest.$ac_ext
+fi
+
+fi
+echo "$as_me:$LINENO: result: $pgac_cv_printf_arg_control" >&5
+echo "${ECHO_T}$pgac_cv_printf_arg_control" >&6
+
+# cross compiler should use our snprintf too
+if test $pgac_cv_printf_arg_control != yes ; then
+  pgac_need_repl_snprintf=yes
+fi
 
 # Check whether <stdio.h> declares snprintf() and vsnprintf(); if not,
 # include/c.h will provide declarations.  Note this is a separate test