Per the accepted answer to this closely-related question, I installed Atom editor on my LinuxMint 18.3 Cinnamon machine using LinuxMint's Software Manager (mintinstall 7.8.9).
I want to install packages and open files from the command line, but BASH raises "command not found" or "program not installed" errors when I try to "apm install foo" or "atom baz.py". I am aware that it's possible to install packages through atom's GUI (ctrl+shift+p ; "Install Packages and Themes"), but I want to get the shell commands up and running.
Unfortunately, even after I figured out where Software Manager put the executables I needed, their behavior was inconsistent. "atom" failed to run, citing a bad path or nonexistent file error on line 5. "atom-real" would run, but didn't reflect the same state I got when I choose atom from the menu or panel. With such poor results, I chose not to update #PATH.
Something's broken, and I'm not sure where to go from here. My apologies for failing to track all error messages - hopefully my approximations are close enough.