Sandboxed process vs writable filesystem locations

https://developer.apple.com/library/archive/qa/qa1811/_index.html

this is old, i know. can those in the know shed some light on whether the bit about temp/cached location still correct:

Code Block
An AudioServerPlugIn operates in a limited environment. ... Further, the host process is sandboxed. As such, an AudioServerPlugIn may only read files in its bundle in addition to the system libraries and frameworks. It may not access user documents or write to any filesystem locations other than the system's cache and temporary directories as derived through Apple API.


i tried to write to temporary folder (obtained with NSTemporaryDirectory and also tried /tmp and /private/tmp) and cached folder (obtained with NSSearchPathForDirectoriesInDomains + cachesDirectory) but everything i tried resulted in permission errors.
Could you file a bug report (with some code snippets showing the actual APIs you're using to get access to the folders), and post the bug number here, please?
created FB8908465

i tried locations obtained with NSTemporaryDirectory (also /tmp /private/tmp /var/tmp) and
NSSearchPathForDirectoriesInDomains + .cachesDirectory in with user, local, network and system domains.
consistently getting this error:
NSCocoaErrorDomain Code=513 "You don’t have permission to save the file"

Sandboxed process vs writable filesystem locations
 
 
Q