diff --git a/test/dup_field.c b/test/dup_field.c
new file mode 100644
index 0000000..68198ed
--- /dev/null
+++ b/test/dup_field.c
@@ -0,0 +1,450 @@
+/****************************************************************************
+ * Copyright 2020-2022,2023 Thomas E. Dickey                                *
+ *                                                                          *
+ * Permission is hereby granted, free of charge, to any person obtaining a  *
+ * copy of this software and associated documentation files (the            *
+ * "Software"), to deal in the Software without restriction, including      *
+ * without limitation the rights to use, copy, modify, merge, publish,      *
+ * distribute, distribute with modifications, sublicense, and/or sell       *
+ * copies of the Software, and to permit persons to whom the Software is    *
+ * furnished to do so, subject to the following conditions:                 *
+ *                                                                          *
+ * The above copyright notice and this permission notice shall be included  *
+ * in all copies or substantial portions of the Software.                   *
+ *                                                                          *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
+ * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
+ * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
+ * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
+ *                                                                          *
+ * Except as contained in this notice, the name(s) of the above copyright   *
+ * holders shall not be used in advertising or otherwise to promote the     *
+ * sale, use or other dealings in this Software without prior written       *
+ * authorization.                                                           *
+ ****************************************************************************/
+/*
+ * $Id: dup_field.c,v 1.8 2023/11/11 00:29:10 tom Exp $
+ *
+ * Demonstrate dup_field().
+ */
+
+#include <test.priv.h>
+
+#if USE_LIBFORM
+
+#include <edit_field.h>
+#include <popup_msg.h>
+
+#define DO_DEMO	CTRL('F')	/* actual key for toggling demo-mode */
+#define MY_DEMO	EDIT_FIELD('f')	/* internal request-code */
+
+static char empty[] = "";
+static FIELD *all_fields[100];
+/* *INDENT-OFF* */
+static struct {
+    int code;
+    int result;
+    const char *help;
+} commands[] = {
+    { CTRL('A'),     REQ_BEG_FIELD,   "go to beginning of field" },
+    { CTRL('D'),     REQ_DOWN_FIELD,  "move downward to field" },
+    { CTRL('E'),     REQ_END_FIELD,   "go to end of field" },
+    { CTRL('H'),     REQ_DEL_PREV,    "delete previous character" },
+    { CTRL('I'),     REQ_NEXT_FIELD,  "go to next field" },
+    { CTRL('K'),     REQ_CLR_EOF,     "clear to end of field" },
+    { CTRL('N'),     REQ_NEXT_FIELD,  "go to next field" },
+    { CTRL('P'),     REQ_PREV_FIELD,  "go to previous field" },
+    { CTRL('Q'),     MY_QUIT,         "exit form" },
+    { CTRL('U'),     REQ_UP_FIELD,    "move upward to field" },
+    { CTRL('W'),     REQ_NEXT_WORD,   "go to next word" },
+    { CTRL('X'),     REQ_CLR_FIELD,   "clear field" },
+    { CTRL('['),     MY_QUIT,         "exit form" },
+    { KEY_F(1),      MY_HELP,         "show this screen", },
+    { KEY_BACKSPACE, REQ_DEL_PREV,    "delete previous character" },
+    { KEY_BTAB,      REQ_PREV_FIELD,  "go to previous field" },
+    { KEY_DOWN,      REQ_DOWN_CHAR,   "move down 1 character" },
+    { KEY_END,       REQ_LAST_FIELD,  "go to last field" },
+    { KEY_HOME,      REQ_FIRST_FIELD, "go to first field" },
+    { KEY_LEFT,      REQ_LEFT_CHAR,   "move left 1 character" },
+    { KEY_NEXT,      REQ_NEXT_FIELD,  "go to next field" },
+    { KEY_PREVIOUS,  REQ_PREV_FIELD,  "go to previous field" },
+    { KEY_RIGHT,     REQ_RIGHT_CHAR,  "move right 1 character" },
+    { KEY_UP,        REQ_UP_CHAR,     "move up 1 character" },
+    { DO_DEMO,       MY_DEMO,         "duplicate current field" }
+};
+/* *INDENT-ON* */
+
+static void
+my_help_edit_field(void)
+{
+    int used = 0;
+    unsigned n;
+    char **msgs = typeCalloc(char *, 3 + SIZEOF(commands));
+
+    msgs[used++] = strdup("Defined form edit/traversal keys:");
+    for (n = 0; n < SIZEOF(commands); ++n) {
+	char *msg;
+	const char *name;
+	const char *code = keyname(commands[n].code);
+	size_t need = 5;
+#ifdef NCURSES_VERSION
+	if ((name = form_request_name(commands[n].result)) == 0)
+#endif
+	    name = commands[n].help;
+	need = 5 + strlen(code) + strlen(name);
+	msg = typeMalloc(char, need);
+	_nc_SPRINTF(msg, _nc_SLIMIT(need) "%s -- %s", code, name);
+	msgs[used++] = msg;
+    }
+    msgs[used++] =
+	strdup("Arrow keys move within a field as you would expect.");
+    msgs[used] = 0;
+    popup_msg2(stdscr, msgs);
+    for (n = 0; msgs[n] != 0; ++n) {
+	free(msgs[n]);
+    }
+    free(msgs);
+}
+
+static FIELD *
+make_label(const char *label, int frow, int fcol)
+{
+    FIELD *f = new_field(1, (int) strlen(label), frow, fcol, 0, 0);
+
+    if (f) {
+	set_field_buffer(f, 0, label);
+	set_field_opts(f, (int) ((unsigned) field_opts(f) & (unsigned) ~O_ACTIVE));
+    }
+    return (f);
+}
+
+static FIELD *
+make_field(int frow, int fcol, int rows, int cols)
+{
+    FIELD *f = new_field(rows, cols, frow, fcol, 0, 1);
+
+    if (f) {
+	set_field_back(f, A_UNDERLINE);
+	init_edit_field(f, empty);
+    }
+    return (f);
+}
+
+static void
+erase_form(FORM *f)
+{
+    WINDOW *w = form_win(f);
+    WINDOW *s = form_sub(f);
+
+    unpost_form(f);
+    werase(w);
+    wrefresh(w);
+    delwin(s);
+}
+
+static FieldAttrs *
+my_field_attrs(FIELD *f)
+{
+    return (FieldAttrs *) field_userptr(f);
+}
+
+static int
+buffer_length(FIELD *f)
+{
+    return my_field_attrs(f)->row_lengths[0];
+}
+
+static void
+set_buffer_length(FIELD *f, int length)
+{
+    my_field_attrs(f)->row_lengths[0] = length;
+}
+
+static int
+offset_in_field(FORM *form)
+{
+    FIELD *field = current_field(form);
+    int currow, curcol;
+
+    form_getyx(form, currow, curcol);
+    return curcol + currow * (int) field->dcols;
+}
+
+static void
+inactive_field(FIELD *f)
+{
+    set_field_back(f, my_field_attrs(f)->background);
+}
+
+static int
+my_edit_field(FORM *form, int *result)
+{
+    int ch = wgetch(form_win(form));
+    int status;
+    FIELD *before;
+    unsigned n;
+    int before_row;
+    int before_col;
+    int before_off = offset_in_field(form);
+
+    form_getyx(form, before_row, before_col);
+    before = current_field(form);
+    set_field_back(before, A_NORMAL);
+    if (ch <= KEY_MAX) {
+	set_field_back(before, A_REVERSE);
+    } else if (ch <= MAX_FORM_COMMAND) {
+	inactive_field(before);
+    }
+
+    *result = ch;
+    for (n = 0; n < SIZEOF(commands); ++n) {
+	if (commands[n].code == ch) {
+	    *result = commands[n].result;
+	    break;
+	}
+    }
+
+    status = form_driver(form, *result);
+
+    if (status == E_OK) {
+	bool modified = TRUE;
+	int length = buffer_length(before);
+
+	if (length < before_off)
+	    length = before_off;
+	switch (*result) {
+	case REQ_CLR_EOF:
+	    length = before_off;
+	    break;
+	case REQ_CLR_EOL:
+	    if ((int) (before_row + 1) == (int) (before->rows))
+		length = before_off;
+	    break;
+	case REQ_CLR_FIELD:
+	    length = 0;
+	    break;
+	case REQ_DEL_CHAR:
+	    if (length > before_off)
+		--length;
+	    break;
+	case REQ_DEL_PREV:
+	    if (length > 0) {
+		if (before_col > 0) {
+		    --length;
+		} else if (before_row > 0) {
+		    length -= (int) before->cols + before_col;
+		}
+	    }
+	    break;
+	case REQ_NEW_LINE:
+	    length += (int) before->cols;
+	    break;
+
+	default:
+	    modified = (ch < MIN_FORM_COMMAND
+			&& isprint(ch));
+	    break;
+	}
+
+	/*
+	 * If we do not force a re-validation, then field_buffer 0 will
+	 * be lagging by one character.
+	 */
+	if (modified && form_driver(form, REQ_VALIDATION) == E_OK && *result
+	    < MIN_FORM_COMMAND)
+	    ++length;
+
+	set_buffer_length(before, length);
+    }
+
+    if (current_field(form) != before)
+	inactive_field(before);
+    return status;
+}
+
+static FIELD **
+copy_fields(FIELD **source, FIELD *extra, size_t length)
+{
+    FIELD **target = typeCalloc(FIELD *, length + 1);
+    memcpy(target, source, length * sizeof(FIELD *));
+    target[length] = extra;
+    return target;
+}
+
+static void
+do_demo(FORM *form)
+{
+    int count = field_count(form);
+    FIELD *my_field = current_field(form);
+    FIELD **old_fields = form_fields(form);
+
+    if (count > 0 && old_fields != NULL && my_field != NULL) {
+	FIELD **new_fields = copy_fields(old_fields,
+					 dup_field(my_field,
+						   form_field_row(my_field)
+						   + 1,
+						   form_field_col(my_field)),
+					 (size_t) count);
+	if (new_fields != NULL)
+	    set_form_fields(form, new_fields);
+    }
+}
+
+static int
+my_form_driver(FORM *form, int c)
+{
+    switch (c) {
+    case MY_QUIT:
+	if (form_driver(form, REQ_VALIDATION) == E_OK)
+	    return (TRUE);
+	break;
+    case MY_HELP:
+	my_help_edit_field();
+	break;
+    case MY_DEMO:
+	do_demo(form);
+	break;
+    default:
+	beep();
+	break;
+    }
+    return (FALSE);
+}
+
+static void
+demo_forms(void)
+{
+    FORM *form;
+    int c;
+    unsigned n = 0;
+    const char *fname;
+
+    /* describe the form */
+    all_fields[n++] = make_label("Sample Form", 0, 15);
+
+    fname = "Last Name";
+    all_fields[n++] = make_label(fname, 2, 0);
+    all_fields[n++] = make_field(3, 0, 1, 18);
+    set_field_type(all_fields[n - 1], TYPE_ALPHA, 1);
+
+    fname = "First Name";
+    all_fields[n++] = make_label(fname, 2, 20);
+    all_fields[n++] = make_field(3, 20, 1, 12);
+    set_field_type(all_fields[n - 1], TYPE_ALPHA, 1);
+
+    fname = "Middle Name";
+    all_fields[n++] = make_label(fname, 2, 34);
+    all_fields[n++] = make_field(3, 34, 1, 12);
+    set_field_type(all_fields[n - 1], TYPE_ALPHA, 1);
+
+    fname = "Comments";
+    all_fields[n++] = make_label(fname, 5, 0);
+    all_fields[n++] = make_field(6, 0, 4, 46);
+    init_edit_field(all_fields[n - 1], empty);
+
+    all_fields[n] = (FIELD *) 0;
+
+    if ((form = new_form(all_fields)) != 0) {
+	int finished = 0;
+
+	post_form(form);
+
+	while (!finished) {
+	    switch (my_edit_field(form, &c)) {
+	    case E_OK:
+		break;
+	    case E_UNKNOWN_COMMAND:
+		finished = my_form_driver(form, c);
+		break;
+	    default:
+		beep();
+		break;
+	    }
+	}
+
+	erase_form(form);
+
+	free_form(form);
+    }
+    for (c = 0; all_fields[c] != 0; c++) {
+	free_edit_field(all_fields[c]);
+	free_field(all_fields[c]);
+    }
+    noraw();
+    nl();
+}
+
+static void
+usage(int ok)
+{
+    static const char *msg[] =
+    {
+	"Usage: dup_field [options]"
+	,""
+	,USAGE_COMMON
+    };
+    size_t n;
+
+    for (n = 0; n < SIZEOF(msg); n++)
+	fprintf(stderr, "%s\n", msg[n]);
+
+    ExitProgram(ok ? EXIT_SUCCESS : EXIT_FAILURE);
+}
+/* *INDENT-OFF* */
+VERSION_COMMON()
+/* *INDENT-ON* */
+
+int
+main(int argc, char *argv[])
+{
+    int ch;
+
+    while ((ch = getopt(argc, argv, OPTS_COMMON)) != -1) {
+	switch (ch) {
+	case OPTS_VERSION:
+	    show_version(argv);
+	    ExitProgram(EXIT_SUCCESS);
+	default:
+	    usage(ch == OPTS_USAGE);
+	    /* NOTREACHED */
+	}
+    }
+    if (optind < argc)
+	usage(FALSE);
+
+    setlocale(LC_ALL, "");
+
+    initscr();
+    cbreak();
+    noecho();
+    raw();
+    nonl();			/* lets us read ^M's */
+    intrflush(stdscr, FALSE);
+    keypad(stdscr, TRUE);
+
+    if (has_colors()) {
+	start_color();
+	init_pair(1, COLOR_WHITE, COLOR_BLUE);
+	init_pair(2, COLOR_GREEN, COLOR_BLACK);
+	init_pair(3, COLOR_CYAN, COLOR_BLACK);
+	bkgd((chtype) COLOR_PAIR(1));
+	refresh();
+    }
+
+    demo_forms();
+
+    endwin();
+    ExitProgram(EXIT_SUCCESS);
+}
+
+#else
+int
+main(void)
+{
+    printf("This program requires the curses form library\n");
+    ExitProgram(EXIT_FAILURE);
+}
+#endif