Does FileWrite/FileRead need a LOCK ?

 

As the tile,

if we need to write in or read from a same file.

do we need to lock them while writing or reading ?

Is that possible when a file is half writen, then only the half writen part is read ?

If we do need a lock , then how can i lock it ...I can find no function about it.

Thanks a lot for your help.

Reason: