Macintosh Operating Systems

The current Mac operating system is macOS, previously named “Mac OS X” prior to 2016. macOS makes use of the BSD codebase, XNU kernel, and Apple’s open source Darwin operating system.

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Terminal Command Reference

Flush DNS

dscacheutil -flushcache

Essential build utilities (gcc, make, …)

xcode-select --install

PERL

Installing custom packages

brew install cpanm
sudo cpanm install <PACKAGE>

RUBY / RVM

Installing older versions of Ruby from Yosemite

brew install gcc48
rvm install 1.9.3