[C] strcpy source code

strcpy.c   [plain text]

/*
 * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * The contents of this file constitute Original Code as defined in and
 * are subject to the Apple Public Source License Version 1.1 (the
 * "License").  You may not use this file except in compliance with the
 * License.  Please obtain a copy of the License at
 * http://www.apple.com/publicsource and read it before using this file.
 * 
 * This Original Code and all software distributed under the License are
 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/* Copyright (c) 1992, 1997 NeXT Software, Inc.  All rights reserved.
 * 
 *  File:   libc/gen/ppc/strcpy.c
 *
 *  This file contains machine dependent code for string copy
 *
 * HISTORY
 *  24-Jan-1997 Umesh Vaishampayan (umeshv@NeXT.com)
 *  Ported to PPC.
 * 24-Nov-92  Derek B Clegg (dclegg@next.com)
 *  Created.
 */
#import <string.h>

/* XXX This routine should be optimized. */

/* ANSI sez:
 *   The `strcpy' function copies the string pointed to by `s2' (including
 *   the terminating null character) into the array pointed to by `s1'.
 *   If copying takes place between objects that overlap, the behavior
 *   is undefined.
 *   The `strcpy' function returns the value of `s1'.  [4.11.2.3]
 */
char *
strcpy(char *s1, const char *s2)
{
    char *s = s1;    /* s1 assign address to s */
    while ((*s++ = *s2++) != 0)   /* s++ only the address of s plus one */
    ;
    return (s1);
}

Reference :

1. strcpy.c

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[C] source code - strcmp.c

/*
 * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * The contents of this file constitute Original Code as defined in and
 * are subject to the Apple Public Source License Version 1.1 (the
 * "License").  You may not use this file except in compliance with the
 * License.  Please obtain a copy of the License at
 * http://www.apple.com/publicsource and read it before using this file.
 * 
 * This Original Code and all software distributed under the License are
 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/* Copyright (c) 1992, 1997 NeXT Software, Inc.  All rights reserved.
 * 
 *  File:   libc/gen/ppc/strcmp.c
 *
 *  This file contains machine dependent code for string comparison
 *  on NeXT 88K-based products.
 *
 * HISTORY
 *  24-Jan-1997 Umesh Vaishampayan (umeshv@NeXT.com)
 *  Ported to PPC.
 * 24-Nov-92  Derek B Clegg (dclegg@next.com)
 *  Created.
 */
#import <string.h>

/* This routine should be optimized. */

/* ANSI sez:
 *   The `strcmp' function compares the string pointed to by `s1' to the
 *   string pointed to by `s2'.
 *   The `strcmp' function returns an integer greater than, equal to, or less
 *   than zero, according as the string pointed to by `s1' is greater than,
 *   equal to, or less than the string pointed to by `s2'.  [4.11.4.2]
 */
int
strcmp(const char *s1, const char *s2)
{
    for ( ; *s1 == *s2; s1++, s2++)
    if (*s1 == '\0')
        return 0;
    return ((*(unsigned char *)s1 < *(unsigned char *)s2) ? -1 : +1);
}

Reference:

1. strcmp.c

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[Interview] pointer concept & (p++ & ++p)

[Interview] pointer concept & (p++ & ++p)

Skill :

1. How to use p++ & ++p

2. Pointer concept

#include<stdio.h>

int main()
{
    int a[]={6,7,8,9,10};
    int *p = a;

    printf("%d \n",*p);

    *(p++)+=123;
    int i = 0;

    printf(" \n\n");

    for (i = 0; i < 5 ; i++)
    {
        printf("%d \n",a[i]);
    }

    printf(" \n\n");
    *(++p)+=123;

    for (i = 0; i < 5 ; i++)
    {
        printf("%d \n",a[i]);
    }

    return 0;
}

6


129
7
8
9
10


129
7
131
9
10

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[面試] 面試技巧

1.請先簡單自我介紹一下.

2.為何想要進入這樣的產業.

3.對這個產業了解多少.

4.為何離開先前的工作.

5.先前的工作,你學到什麼.

6.1~10 你對自己的自信打幾分.

7.說說應試者,你有沒有曾經想要得到.而真的得到的經驗

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