Eclipse IDE for C/C++ Developers 开发c

http://sourceforge.net/projects/mingw/files/  下载

 

 

opencv　函数

http://www.cnblogs.com/skyseraph/archive/2011/05/23/2054592.html

 

WinGW

下载 Eclipse IDE for C/C++ Developers 

 

Fat Jar     打包工具

 

 

c  int  4 字节(4*8=32bit)

 

int a ＝ 9；

int ＊b；

b＝&a; 

 

printf("%d\n", a); 9

printf("%d\n", *b); 9

         printf("%d\n", b); //2293576

1,指针方便操作  能动态变换值 function (int *b ) 一般*b 是要处理后出来值变化的

|        |<----*b (包含两个属性 指针的地址 和 指向的值)

|        |

|        |

 

 

 

 

 

 

 

char *revstr(char *str, size_t len)
{
    char    *start = str;
    char    *end = str + len - 1;
    char    ch;
    if (str != NULL)
    {
        while (start < end)
        {
             ch = *start;
            *start++ = *end;
            *end-- = ch;
        }
    }
    return str;
}

void main(void) {
  char * a ="hello"; // 错误 

char  a[10] ="hello";

  printf("%s",revstr(a,strlen(a)));

}

fopen(path, "a+")  没有的话创建新文件写道

VC++ #include "stdafx.h" F5 build debug F10 F11 getchar(); 命令窗口停住
strlen(a)计算长度数组

extern "C" {
#endif/*_cplusplus*/
	
	typedef struct comp{		
		unsigned char	*source;
		unsigned short	sLen;	
		unsigned char	*dest;
		unsigned short	dLen;
		unsigned char	*seed;
		unsigned short	seedLen;
		char			*compBuf;
	}OK;
	
	extern OK 	compData ;
	
	extern short	MSendData( const char *path );
	extern void		Compress(OK *compData );
#ifdef __cplusplus
}

  #include <sys/stat.h>

#include <sys/types.h> 

struct stat st;
	 stat(path, &st);

	 int filesize = st.st_size;
	char* data = (char*)malloc(filesize); //分配内存
	 	printf("the fopen2 is: %s \n",path);
	 	fp = fopen(path, "rb");
//	 	if( (fp = fopen(path, "a+")) )
//	 	{
	 		printf("the fopen3 is: %s \n",path);
	 		fread(data, filesize, 1, fp);
	 		printf("the fopen3 is: %s  %d \n",data,filesize);
//	 	}