Write movement manualy to g-code with linuxcnc

Hi, all.

I have very interesting task to realize.
On my CNC machine I want to set encoders and to move spindle manualy. And linuxcnc should write this coordinates to file as G-code for each axis. After that I want to open this file and to make run in linuxcnc program.

How can I make this? I know that it's far from default task of linuxcnc - read encoder inputs and write them to the file. Or I need to write my own program in Pyton where I should use HAL only? Please give me an advise of that.
As for hardware I want to use Mesa cards for this. Motors will be controled with analog singal to servodrives.

this is called probe result
look into here

there are ready made NGC and functions to probe a part in a boundery

This is called teach-in on some controllers,
Here is LinuxCNC implementation forum.linuxcnc.org/forum/21-axis/30986-a...osition-logger#74810