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diff --git a/builtins/shift.def b/builtins/shift.def
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+This file is shift.def, from which is created shift.c.
+It implements the builtin "shift" in Bash.
+
+Copyright (C) 1987-2020 Free Software Foundation, Inc.
+
+This file is part of GNU Bash, the Bourne Again SHell.
+
+Bash 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.
+
+Bash 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 Bash.  If not, see <http://www.gnu.org/licenses/>.
+
+$PRODUCES shift.c
+
+#include <config.h>
+
+#if defined (HAVE_UNISTD_H)
+#  ifdef _MINIX
+#    include <sys/types.h>
+#  endif
+#  include <unistd.h>
+#endif
+
+#include "../bashansi.h"
+#include "../bashintl.h"
+
+#include "../shell.h"
+#include "common.h"
+
+$BUILTIN shift
+$FUNCTION shift_builtin
+$SHORT_DOC shift [n]
+Shift positional parameters.
+
+Rename the positional parameters $N+1,$N+2 ... to $1,$2 ...  If N is
+not given, it is assumed to be 1.
+
+Exit Status:
+Returns success unless N is negative or greater than $#.
+$END
+
+int print_shift_error;
+
+/* Shift the arguments ``left''.  Shift DOLLAR_VARS down then take one
+   off of REST_OF_ARGS and place it into DOLLAR_VARS[9].  If LIST has
+   anything in it, it is a number which says where to start the
+   shifting.  Return > 0 if `times' > $#, otherwise 0. */
+int
+shift_builtin (list)
+     WORD_LIST *list;
+{
+  intmax_t times;
+  int itimes, nargs;
+
+  CHECK_HELPOPT (list);
+
+  if (get_numeric_arg (list, 0, &times) == 0)
+    return (EXECUTION_FAILURE);
+
+  if (times == 0)
+    return (EXECUTION_SUCCESS);
+  else if (times < 0)
+    {
+      sh_erange (list ? list->word->word : NULL, _("shift count"));
+      return (EXECUTION_FAILURE);
+    }
+  nargs = number_of_args ();
+  if (times > nargs)
+    {
+      if (print_shift_error)
+	sh_erange (list ? list->word->word : NULL, _("shift count"));
+      return (EXECUTION_FAILURE);
+    }
+  else if (times == nargs)
+    clear_dollar_vars ();
+  else
+    shift_args (itimes = times);
+
+  invalidate_cached_quoted_dollar_at ();
+
+  return (EXECUTION_SUCCESS);
+}