add man page, cleanup

[unix-history] / usr / src / usr.bin / rev / rev.c

/*
* Copyright (c) 1987 Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by the University of California, Berkeley.  The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/

#ifndef lint
char copyright[] =
"@(#) Copyright (c) 1987 Regents of the University of California.\n\
All rights reserved.\n";
#endif /* not lint */

#ifndef lint
static char sccsid[] = "@(#)rev.c       4.4 (Berkeley) %G%";
#endif /* not lint */

#include <stdio.h>

main(argc, argv)
       int argc;
       char **argv;
{
       register char *t, *bp;
       char buf[BUFSIZ];

       bp = buf;
       do {
               if (argc > 1 && !freopen(*++argv, "r", stdin)) {
                       fprintf(stderr, "rev: cannot open %s.\n", *argv);
                       exit(1);
               }
               while (fgets(bp, sizeof(buf), stdin)) {
                       for (t = bp; *t; ++t);
                       if (*--t == '\n')
                               --t;
                       for (; t >= bp; --t)
                               putchar(*t);
                       putchar('\n');
               }
       } while(--argc > 1);
       exit(0);
}