Returns what number in a link set the script is attached to (0 means no link, 1 the root/parent, 2 for first child, etc).
Links are numbered in the reverse order in which they were linked -- if you select a box, a sphere and a cylinder in that order, then link them, the cylinder is 1, the sphere is 2 and the box is 3. The last selected prim has the lowest link number.
Compare with llGetLinkName
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