d.p.carlisle at gmail.com
Sat Oct 20 23:22:11 CEST 2018
On Sat, 20 Oct 2018 at 22:12, Hefferon, Jim S. <jhefferon at smcvt.edu> wrote:
> I'm trying to understand the \write<number> command, specifically \write16 and \write17. I'd appreciate any help.
> I understand that the output files are ordinarily numbered 1 to 15,
> and that if <number> is positive and outside that range then TeX writes to both the log file and the terminal. So I think I understand that \write16 was adopted early on as a convention to write to both. I see it in the TeXbook. Is that understanding right?
yes although I don't think there is or was any particular convention to use 16.
> But \write17? Google gives me a references to it, but what is it for? How is it different than \write16?
It's the same as you say, the same as any value > 15 (in classic tex)
> If it is no different then why was it skipped over in getting to \write18?
I wasn't there but I think it's just a "margin of error" to make it
less likely to clash with existing use when the shell-escape system
> (I know that \write18 is an entirely different animal.)
> Thank you,
In luatex there are 256 rather than 16 output streams, so it's different again.
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