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1. ij32λϵͳÏÂ, C++³ÌÐò£¬Çë¼ÆËãsizeof µÄÖµ
#include <stdio.h>
#include <malloc.h>
void Foo ( char str[100] )
{
    printf("sizeof(str)=%d \n", sizeof(str) );//´Ë´¦Ê¹ÓÃchar *strÓëchar str[100]ÊÇÒ»ÑùµÄ£¬char str[100]²»Ö¸Ã÷´óС(char str[])Ò²ÐÐ,ÒòΪ±àÒëÆ÷ÊÇ°ÑËüµ±×ö Ò»¸öÖ¸ÕëÀ´´¦ÀíµÄ
}
main()
{
    char str[] = "www.ibegroup.com";
    char *p1 = str ;
    int n = 10;
    void *p2 = malloc( 100 );
    printf("sizeof(str)=%d \n", sizeof(str) );
    printf("sizeof(p1)=%d \n", sizeof(p1) );
    printf("sizeof(n)=%d \n", sizeof(n) );
    printf("sizeof(p2)=%d \n", sizeof(p2) );
    Foo(str);//Êý×éÃûÏ൱ÓÚÒ»¸öÖ¸Õ룬ָÕëµÄ´óСΪ4£¬ËùÒÔÊä³ö4¶ø²»ÊÇ17£¬ÁíÍâsizeof ÊǼÆËãÀàÐͳ¤¶ÈµÄ£¬strlen ²ÅÊǼÆËã×Ö·û´®³¤¶ÈµÄ}
}
´ð£º(1)17  (2)4   (3) 4   (4)4   (5)4
2.  »Ø´ðÏÂÃæµÄÎÊÌâ
(1) Í·ÎļþÖÐµÄ ifndef/define/endif¸ÉʲôÓÃ? Ô¤´¦Àí
´ð£º·ÀֹͷÎļþ±»Öظ´ÒýÓÃ
(2) #include <filename.h> ºÍ #include "filename.h" ÓÐʲôÇø±ð?
´ð£º
¶ÔÓÚ#include <filename.h> £¬±àÒëÆ÷´Ó±ê×¼¿â·¾¶¿ªÊ¼ËÑË÷filename.h
¶ÔÓÚ#include "filename.h" £¬±àÒëÆ÷´ÓÓû§µÄ¹¤×÷·¾¶¿ªÊ¼ËÑË÷filename.h
(3) ÔÚC++ ³ÌÐòÖе÷Óñ» C ±àÒëÆ÷±àÒëºóµÄº¯Êý£¬ÎªÊ²Ã´Òª¼Ó extern “C”ÉùÃ÷?
´ð£ºº¯ÊýºÍ±äÁ¿±»C++±àÒëºóÔÚ·ûºÅ¿âÖеÄÃû×ÖÓëCÓïÑԵIJ»Í¬£¬±»extern "C"ÐÞÊεıäÁ¿ºÍº¯ÊýÊÇ°´ÕÕCÓïÑÔ·½Ê½±àÒëºÍÁ¬½ÓµÄ¡£ÓÉÓÚ±àÒëºóµÄÃû×Ö²»Í¬£¬C++³ÌÐò²»ÄÜÖ±½Óµ÷ÓÃC º¯Êý¡£C++ÌṩÁËÒ»¸öC Á¬½Ó½»»»Ö¸¶¨·ûºÅextern“C”À´½â¾öÕâ¸öÎÊÌâ¡£
3.  »Ø´ðÏÂÃæµÄÎÊÌâ
(1)  ÇëÎÊÔËÐÐTest º¯Êý»áÓÐʲôÑùµÄ½á¹û?
Void GetMemory(char **p, int num)
{
    *p = (char *)malloc(num);
}
void Test(void)
{
    char *str = NULL;
    GetMemory(&str, 100);
    strcpy(str, "hello");
    printf(str);
}
´ð£ºÊä³ö“hello”