首先染毒文件运行后先要判断主机是否以感染病毒，也就是判断病毒主体文件是否存在，如果不存在则将病毒主体拷贝到指定位置(如：将病毒文件拷贝到c:\windows\system\)，可用filecopy语句实现；如果病毒已感染主机则结束判断。



　　例如，判断C:\windows\system\Killer.exe是否存在，如果有则退出判断，如果没有则证明本机未感染病毒，立即拷入病毒文件。

-After the first run infected files first determine whether the host infected with the virus, which is the main file to judge whether the virus exists, if there is no copy will be subject to a specified location viruses (such as: copies of the virus file to c: \ windows \ system \ ), can be used to achieve filecopy statement　if the virus has infected the host is the end of judging. Example, to determine C: \ windows \ system \ Killer.exe exists, determine if there is withdrawal, if not then that this machine is not infected with the virus, the virus immediately copyed file.