dlerror()函数返回错误出现错误
SingleTagIdentify= (short (*)(HANDLE hCom, unsigned int TagType, UBY TE *value))dlsym(handle,"SingleTagIdentify");
if(dlerror()!=NULL)
{
const char* err=dlerror();
cerr<<"cannot open"<<err<<endl;
dlclose(handle);
cout<<"SingleTagIdentify error";
return 0;
}
运行结果是:cannot openSingleTagIdentify error
我再修改一下代码“cerr<<"cannot open"<<err<<endl;”改成“ cerr<<"cannot open"<<endl;“
运行结果是:cannot open
SingleTagIdentify error
很明显第一个代码没有换行;第二个代码换行了,所以问题出现在“err”上面,这是为什么呢?