locate.bigram.c revision 8874 
1/*
2 * Copyright (c) 1989, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * James A. Woods.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 *    must display the following acknowledgement:
18 *	This product includes software developed by the University of
19 *	California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 *    may be used to endorse or promote products derived from this software
22 *    without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 */
36
37#ifndef lint
38static char copyright[] =
39"@(#) Copyright (c) 1989, 1993\n\
40	The Regents of the University of California.  All rights reserved.\n";
41#endif /* not lint */
42
43#ifndef lint
44static char sccsid[] = "@(#)locate.bigram.c	8.1 (Berkeley) 6/6/93";
45#endif /* not lint */
46
47/*
48 *  bigram < text > bigrams
49 *
50 * List bigrams for 'updatedb' script.
51 * Use 'code' to encode a file using this output.
52 */
53
54#include <stdio.h>
55#include <sys/param.h>			/* for MAXPATHLEN */
56
57char buf1[MAXPATHLEN] = " ";
58char buf2[MAXPATHLEN];
59
60main ( )
61{
62  	register char *cp;
63	register char *oldpath = buf1, *path = buf2;
64
65     	while ( fgets ( path, sizeof(buf2), stdin ) != NULL ) {
66
67		/* skip longest common prefix */
68		for ( cp = path; *cp == *oldpath; cp++, oldpath++ )
69			if ( *oldpath == NULL )
70				break;
71		/*
72		 * output post-residue bigrams only
73		 */
74		while ( *cp != NULL && *(cp + 1) != NULL ) {
75			putchar ( *cp++ );
76			putchar ( *cp++ );
77			putchar ( '\n' );
78		}
79		if ( path == buf1 )		/* swap pointers */
80			path = buf2, oldpath = buf1;
81		else
82			path = buf1, oldpath = buf2;
83   	}
84}
85