<operating system, abuse> The sort the speaker is used to. People from the BSDophilic academic community are likely to issue comments like "System V? Why don't you use a *real* operating system?", people from the commercial/industrial Unix sector are known to complain "BSD? Why don't you use a *real* operating system?", and people from IBM object "Unix? Why don't you use a *real* operating system?"
See holy wars, religious issues, proprietary, Get a real computer!.
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Nearby terms: realization « real mode « real number « real operating system » Real Programmer » Real Programmers Don't Use Pascal » Real Soon Now