Deleting roms on sd card after copying files to usb stick

[Solominator]

Hi there, sorry for my bad english...

I installed my retropie to a 32GB sd card. Now it's nearly full an i transfered the roms to a usb stick.
Anything works fine.
Now I search a way to delete the old rom files on the sd card... but can find them in the file manager.
What is the path to the rom files on the sd card?

[jonnykesh]

@solominator /home/pi/RetroPie/roms/$system_name/

[Solominator]

...I think it was my fault...
I was thinking, that retropie shows me the usb files, when i plug in the stick...
But it look like, it shows alltime the files on the sd card ;-)
...so I have created a folder "retropie-mount" on the usb stick, let retropie copy all roms to it, and after that I deleted any files in "\retropie\roms"
Look like this solve my issue.

I think now I understand the differents between the directory "retropie" and "retropie-mount"
...if I want to import roms to the sd card, i put the files on the usb stick to "retropie" and if I like to use a external usb stick as storage for the roms, I use the "retropie-mount" directory on the usb stick...
Is this right?