xref: /freebsd/contrib/nvi/ex/ex_equal.c (revision 3cbb4cc200f8a0ad7ed08233425ea54524a21f1c)
1 /*-
2  * Copyright (c) 1992, 1993, 1994
3  *	The Regents of the University of California.  All rights reserved.
4  * Copyright (c) 1992, 1993, 1994, 1995, 1996
5  *	Keith Bostic.  All rights reserved.
6  *
7  * See the LICENSE file for redistribution information.
8  */
9 
10 #include "config.h"
11 
12 #include <sys/types.h>
13 #include <sys/queue.h>
14 #include <sys/time.h>
15 
16 #include <bitstring.h>
17 #include <limits.h>
18 #include <stdio.h>
19 
20 #include "../common/common.h"
21 
22 /*
23  * ex_equal -- :address =
24  *
25  * PUBLIC: int ex_equal(SCR *, EXCMD *);
26  */
27 int
28 ex_equal(SCR *sp, EXCMD *cmdp)
29 {
30 	recno_t lno;
31 
32 	NEEDFILE(sp, cmdp);
33 
34 	/*
35 	 * Print out the line number matching the specified address,
36 	 * or the number of the last line in the file if no address
37 	 * specified.
38 	 *
39 	 * !!!
40 	 * Historically, ":0=" displayed 0, and ":=" or ":1=" in an
41 	 * empty file displayed 1.  Until somebody complains loudly,
42 	 * we're going to do it right.  The tables in excmd.c permit
43 	 * lno to get away with any address from 0 to the end of the
44 	 * file, which, in an empty file, is 0.
45 	 */
46 	if (F_ISSET(cmdp, E_ADDR_DEF)) {
47 		if (db_last(sp, &lno))
48 			return (1);
49 	} else
50 		lno = cmdp->addr1.lno;
51 
52 	(void)ex_printf(sp, "%ld\n", lno);
53 	return (0);
54 }
55