从序列号12字节，到longlong, longlong 大小用6字节存蓄十六进制，0x000000e1e2e3 字符串转 longlong sscanf

本文深入探讨了C语言中长整型数值与字符串之间的转换方法，包括使用memcpy、sscanf等函数进行数据操作，并展示了如何通过十六进制字符串表示长整型值。同时，介绍了数据的复制、格式化输出以及从字符串到长整型值的转换过程。

#include "stdio.h"
#include "memory.h"

int main()
{

long long lltest=0x000000a1a2ae;
long long llm=0xa1a2ae;

//printf("%lld\n",lltest);
//printf("%lld\n",llm);

char *str="000654321012";//"3841";//hex 0f01 //"000654321012";
char data[12];
memcpy(data,str,12);
long long ll=0;//987654321012;//12byte

sscanf(data, "%lld", &ll);

printf("%lld",ll);
return 0;

long long lval;
sscanf("0x000000a1a2ae", "%llx", &lval);

printf("%lld\n",lval);

/*
char hex[101];
char s[51];
unsigned int v;
strcpy(hex,"e5f4c8f374"); // 0f11
int L=strlen(hex);
int i;
for (i=0;i<L/2;i++) {
sscanf(hex+i*2,"%2X",&v);
s[i]=(char)(v&0xFFu);
}
s[i]=0;
printf("%s\n",s);

L=strlen(s);
for (i=0;i<L;i++) sprintf(hex+2*i,"%02X",(unsigned char)s[i]);
hex[2*i+2]=0;
printf("%s\n",hex);

return 0;
*/

/*
char *str="3841";//hex 0f01 //"987654321012";

char data[12];
memcpy(data,str,12);

char chs[16];
char UDID[6];

long long llong=0;//987654321012;//12byte

sscanf(data, "%lld", &llong);

sprintf(chs, "%llx", llong); //#llx 0x #is mean 0x
printf("strlen chs:%d\n",strlen(chs));

memcpy(UDID,&llong,6);
printf("%s\n",chs);

int i=0;
for (i;i<6;i++)
{
printf("%x ",UDID[i]);
}
printf("\n");

printf("value:%lld\n",llong);
printf("sizeof longlong :%d\n",sizeof(llong));
return 0; */
}