I have backup of my EFS partitions in raw and also in .Img format.
So now i want to:
- replace my current EFS partitions via Termux/Terminal emulator app.
- replaced EFS should also sync with modem without any reboot.
I have successfully done above via Fastboot and Recovery but that i don't want to.
My Findings:
I found EFS and modem partitions are mounted as modemst1, modemst2, modem and fsg etc in /dev/block/ and /dev/block/by-name.
But replacing them via Termux won't make any difference to actual EFS partitions. Also after reboot these again gets re-created/replaced.
But if i replace all these partitons via Recovery/Fastboot then it make actual permanent changes to EFS partitions and sync with modem and also sustain reboot.