Quick little blurb today..
Today I installed Arduino using homebrew/cask on my laptop, and was running into a little issue...
chmod: Unable to change file mode on /opt/homebrew-cask/Caskroom/arduino/1.6.5-r5/Arduino.app/Contents/Java/hardware/tools/avr/bin/avrdude_bin: Operation not permitted
Part of my issue was that I have an unusual homebrew install (installed with my 'admin' user, but my day to day user is not an admin).
I ended up following the steps outlined on this stackexchange post, and it didn't actually solve my problem, but it got my homebrew setup a lot happier for my non-admin user.
Then, I did the last thing any good programmer will do, and actually read what the error message was telling me! The arduino process was trying to chmod a file, which meant that it's mode must be incorrect...
bash-3.2$ ls -la /opt/homebrew-cask/Caskroom/arduino/1.6.5-r5/Arduino.app/Contents/Java/hardware/tools/avr/bin/avrdude_bin-rw-rw-r-- 1 admin admin 369784 Apr 14 16:30 /opt/homebrew-cask/Caskroom/arduino/1.6.5-r5/Arduino.app/Contents/Java/hardware/tools/avr/bin/avrdude_bin
I did an inspection of all the files in the avr/bin/ directory, and none of them had owner OR group execute permissions!
A quick little command fixed up my issue!
bash-3.2$ chmod g+x /opt/homebrew-cask/Caskroom/arduino/1.6.5-r5/Arduino.app/Contents/Java/hardware/tools/avr/bin/*
I can now load sketches to my Arduino, and connect to the serial port!
Thanks for reading everyone! I hope this helps someone with the same problem!