I vaguely remember years ago someone saying that the a mode in the PHP fopen() call doesn't file locking - is this true?

CodePudding user response：

The documentation does not mention anything about locking.

However, there are some references about the flock function. This function is to be called after fopen as it takes a stream handle as parameter.

It allows to acquire an exclusive lock, or a shared lock. It can also be released manually or automatically when calling fclose on locked resource, or when the said resource is garbage collected.