If the file specified does not exist, then it will be created; otherwise, the new trace information will be appended to the end of the file. However, the path to the file must exist.
If the filename given is invalid or if the file cannot be created or written to, no trace will occur and no error message will be returned.
It is not recommended to use tracing in a multithreaded application, because all the threads will write to the same output file, and the output will be hard to decipher.