strlen.c

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/*
 * strlen.c
 * Modified for use in 15-410 at CMU
 * Zachary Anderson(zra)
 */

/* 
 * Mach Operating System
 * Copyright (c) 1992,1991,1990,1989 Carnegie Mellon University
 * All Rights Reserved.
 * 
 * Permission to use, copy, modify and distribute this software and its
 * documentation is hereby granted, provided that both the copyright
 * notice and this permission notice appear in all copies of the
 * software, derivative works or modified versions, and any portions
 * thereof, and that both notices appear in supporting documentation.
 * 
 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 * 
 * Carnegie Mellon requests users of this software to return to
 * 
 *  Software Distribution Coordinator  or  [e-mail]
 *  School of Computer Science
 *  Carnegie Mellon University
 *  Pittsburgh PA 15213-3890
 * 
 * any improvements or extensions that they make and grant Carnegie Mellon
 * the rights to redistribute these changes.
 */
/*
 * File: 	limach/strlen.c
 * Author:	Robert V. Baron at Carnegie Mellon
 * Date:	Oct 13, 1992
 * Abstract:
 *	strlen returns the number of characters in "string" preceeding 
 *	the terminating null character.
 */

#include <string.h>

int
strlen(const char *string)
{
    const char *ret = string;

    while (*string++);

    return string - 1 - ret;

}