小弟我做了一个壁纸的应用程序，就是把应用程序里面的图片保存到本地文件夹里面。小弟我写完后再模拟器下运行正常，但是把它移植到真机下就保存失败？这是为什么

void SetName(belle *pMe){
    char time[50];
        char temGroup[10];
    char temGroup1[10];
    char temGroup2[10];
    char temGroup3[10];
    char temGroup4[10];
    char temGroup5[10];
            JulianType rJulianDate;
        GETJULIANDATE(0, &rJulianDate);
        DBGPRINTF("wYear=%d,wMonth=%d,wDay=%d,wHour=%d,wMinute=%d,wSecond=%d\n",rJulianDate.wYear,rJulianDate.wMonth,rJulianDate.wDay,rJulianDate.wHour,rJulianDate.wMinute,rJulianDate.wSecond);
        SPRINTF((char*)temGroup, "%d", rJulianDate.wYear);
        SPRINTF((char*)temGroup1, "%d", rJulianDate.wMonth);
        SPRINTF((char*)temGroup2, "%d", rJulianDate.wDay);
                SPRINTF((char*)temGroup3, "%d", rJulianDate.wHour);
        SPRINTF((char*)temGroup4, "%d", rJulianDate.wMinute);
        SPRINTF((char*)temGroup5, "%d", rJulianDate.wSecond);
        DBGPRINTF("%s-%s-%s-%s:%s:%s",temGroup,temGroup1,temGroup2,temGroup3,temGroup4,temGroup5);
                MEMSET(time,0,sizeof(time));
        STRCAT((char*)time,temGroup);
        STRCAT((char*)time,temGroup1);
        STRCAT((char*)time,temGroup2);
        STRCAT((char*)time,temGroup3);
        STRCAT((char*)time,temGroup4);
        STRCAT((char*)time,temGroup5);
        DBGPRINTF("=================%s",time);
                MEMSET(pMe->savefilename,0,sizeof(pMe->savefilename));

STRCAT(pMe->savefilename,"fs:/mod/10888/");
STRCAT(pMe->savefilename,time);
STRCAT(pMe->savefilename,".jpg");
}

void ReadFile(belle *pMe,const char *myfile,const char *savefile)
{    
    int count;
    AEEFileInfo   pInfo;
    AECHAR sh[20] ={'l','i','n','g'}; 
    AECHAR ss[20] ={'s','s','s','s'}; 
        pMe->pMyFile = IFILEMGR_OpenFile(pMe->pMyFileMgr,myfile,_OFM_READ);
    
    if(pMe->pMyFile==NULL){    
        DBGPRINTF("ENTER pMe->pMyFile11 = NULL\n");
        return;    
    }
    
    IFILE_GetInfo(pMe->pMyFile,&pInfo);//读取文件大小
    DBGPRINTF("pMe->pInfo->dwSize=%d\n",pInfo.dwSize);
    
    pMe->mydata=(char *)MALLOC(pInfo.dwSize);//分配动态内存