[DGD]Kernel mudlib question: What's TLS?

[Cathy Willey]

I've been poking through the kernel mudlib with the goal of building my own
extensions onto it, and have one nagging, probably stupid, question:

What exactly is TLS? I see a lot of support for it in the kernel, but
nothing actually uses it, as far as I can tell (I checked - there's a lot of
'tls' variables declared and allocated, but no calls to set_tlvar() or
get_tlvar() ). And there's no documentation on it - so I'm not quite sure what,
exactly, it's supposed to do for me and why I might want to use it. 

Can someone offer a brief explanation of the system?

Thanks in advance,
Cathy Willey

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