The FILE specifier indicates the name of the file to be connected to the unit. It takes the following form:
The name can be any pathname allowed by the operating system.
Any trailing blanks in the name are ignored.
If FILE is omitted and the unit is not connected to a file, the OPEN statement must specify STATUS='SCRATCH'.
If the file name is stored in a numeric scalar or array, the name must consist of ASCII characters terminated by an ASCII null character (zero byte). However, if it is stored in a character scalar or array, it must not contain a zero byte.
For More Information: