date and time created 88/03/23 09:52:47 by karels

[unix-history] / usr / src / local / local.cmd / 20b.c

/*
 * Copyright (c) 1986 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that this notice is preserved and that due credit is given
 * to the University of California at 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'' without express or implied warranty.
 */

#ifndef lint
char copyright[] =
"@(#) Copyright (c) 1986 Regents of the University of California.\n\
 All rights reserved.\n";
#endif /* not lint */

#ifndef lint
static char sccsid[] = "@(#)20b.c	5.3 (Berkeley) %G%";
#endif /* not lint */

#include <stdio.h>

main(argc, argv)
	int argc;
	char **argv;
{
	register int bsize, cc, want;
	register char *base, *current;
	char *alloca();

	if (argc > 1) {
		bsize = atoi(argv[1]);
		if (bsize <= 0) {
			fputs("20b: bad block size.\n", stderr);
			exit(-1);
		}
	}
	base = alloca(bsize);
	for (cc = bsize; cc > 0;) {
		current = base;
		for (want = bsize; want > 0 && cc > 0; want -= cc) {
			if ((cc = read(0, current, want)) < 0)
				return(-1);
			current += cc;
		}
		want = bsize - want;
		if (want && write(1, base, want) != want)
			return(-1);
	}
	return(0);
}