Pretty slick chroot/jail app! I tested it out in the emulator (cc 1.5, advanced computer) with a jailed startup file and no 'ls' or 'dir' commands copied into the jail. (Specifically, no /rom/startup to add those commands or edit the path variable.)
Everything worked exactly as expected!
I even took some screenshots (Feel free to use/edit/whatever. You can go one folder up to 'picts', to right-click save if need be.)
ccbox-1 shows a root folder with no startup file, and a test1 folder that itself contains a startup file and a /test1/rom/programs/shell file (But no other programs.) I am about to hit enter on the command "ccbox /test1"
ccbox-2 shows after hitting enter on the "ccbox /test1" command.
ccbox-3 shows after clicking the green "B" boot button, and shows the /test1/startup program running successfully.
ccbox-4 shows an attempt at running "ls", but as I purposefully did not copy over /rom/startup into the jail, it gives the expected "No such program" error.
Finally, I copied the entire contents of /rom/programs/ to /test1/rom/programs/ and also copied /rom/startup to /test1/rom/startup
and then re-ran "ccbox /test1"
ccbox-5 shows "ls" works as expected this time, and there is no trace of the test1 or test2 folders in the root dir, showing it is indeed jailed inside /test1/