XXX/X-X-X/ A marker that attention is needed. Commonly used in program comments to indicate areas that are kluged or need to be. Some hackers liken "XXX" to the notional heavy-porn movie rating. Compare FIXME. [Jargon File]
X-Windows ♦ X Window System ♦ XWIP ♦ xxgdb ♦ XXX ♦ Xy-pic ♦ xyzzy ♦ Y ♦ Y2K
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