gethostbyaddr segmentation error FAQ

p, li { white-space: pre-wrap; }

struct hostent* hostEnt;

hostEnt=gethostbyaddr(inet_ntoa(ptr->ip_src),sizeof(ptr->ip_src),AF_INET);

if(!hostEnt)
{
tmp=new QStandardItem("No Name");
Row.append(tmp);
}else
{
tmp=new QStandardItem(hostEnt->h_name);
Row.append(tmp);
}
above is right,but before I get to know this issue, I didn't check the hostEnt's value,so when there is no result to return , hostEnt-> operation will throw out segmentation error

note that....