When i use the instruction tail -f filename
it stops after 10 lines and givs error message ( in Danish )

tail:ukendt filsystemtype ox53464846 for ´ALL_2017_10.TXT´.
rapporter venlig dette til bug-coreutils@gnu.org. går over til gentagene
forespørgsler.

And continues to do what is expected.
File type is TXT (aski ) size of file is abaut 2.8 MB ( starting from 0
bytes after a month.)
Number 0x53464846 is the same eacht time i start my Script.

Hope this is useful !

All the best.

Allan Jensen
Gårdager 17
2640-Hedehusene
Denmark

Tlf 045 42 74 40 68