LPR Printing: Tumble mode

Question

Apparently this is an option to do with duplex/simplex in lpr, but I haven't been able to find what it means.

Answer 1

When you print duplex (i.e. double-sided), you have several options as to which direction the reverse should be respective to the converse. Long edge duplex means that you turn the paper along its long edge, so that the up direction is the same on both sides of the paper in portrait orientation. Short edge duplex means that you turn the paper along its short edge, so that the up direction is the same on both sides of the paper in landscape orientation.

 ┌─────┐↷┌─────┐    ┌────────┐↷┌────────┐
 │front│ │back │    │front   │ │back    │
 │     │ │     │    │        │ │        │
 │     │ │     │    └────────┘ └────────┘
 │     │ │     │     short edge (tumble)
 └─────┘ └─────┘
long edge (no tumble)