The AtEndOfFile(file) command returns true if and only if the end of a STREAM file has been reached during a read operation. Otherwise, AtEndOfFile(file) returns false.

The end of file must actually have been encountered. For example, requesting  Read to read 20 bytes when only 19 remain in the file results in a subsequent AtEndOfFile call returning true. When the ReadLine function reads the last line of a file, it does not encounter the end of file; the next call to ReadLine reads the end of file.

If file does not refer to an open file, AtEndOfFile raises an error.