1. The script does not support Unix.
2. In Linux, firstly cd to the directory where the .dat file locate, then run sudo bash ./ExtendPersistentImg.sh ./persistence_pop-os_osint.dat 16384
2. In Linux, firstly cd to the directory where the .dat file locate, then run sudo bash ./ExtendPersistentImg.sh ./persistence_pop-os_osint.dat 16384