What does “opt” mean (as in the “opt” directory)? I commonly see this directory in Unix systems with development tools inside.
Is it an abbreviation?
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What does “opt” mean (as in the “opt” directory)? I commonly see this directory in Unix systems with development tools inside.
Is it an abbreviation?
In the old days, "/opt" was used by UNIX vendors like AT&T, Sun, DEC and 3rd-party vendors to hold "Option" packages; i.e. packages that you might have paid extra money for. I don’t recall seeing "/opt" on Berkeley BSD UNIX. They used "/usr/local" for stuff that you installed yourself.
But of course, the true "meaning" of the different directories has always been somewhat vague. That is arguably a good thing, because if these directories had precise (and rigidly enforced) meanings you’d end up with a proliferation of different directory names.
The Filesystem Hierarchy Standard says this about "/opt/*":
By contrast it says this about "/usr/local/*":
These days, "/usr/local/*" is typically used for installing software that has been built locally, possibly after tweaking configuration options, etcetera.