The CountCharacters(file) command counts the number of characters from file's current position to the end of the file.

The CountCharacters(file, character) command counts the number of occurrences of character from file's current position to the end of the file.

As CountCharacters is a Text function, it counts characters, not bytes.  Therefore characters represented as multiple bytes, (like "\\r\\n") are counted as a single character.  This means the number of characters in a file can differ from the number of bytes in a file.

An error is raised if file is not a valid descriptor or if the filename does not exist.