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diff --git a/Master/texmf-dist/doc/generic/FAQ-en/html/FAQ-write.html b/Master/texmf-dist/doc/generic/FAQ-en/html/FAQ-write.html deleted file mode 100644 index 68fc5cc9dd7..00000000000 --- a/Master/texmf-dist/doc/generic/FAQ-en/html/FAQ-write.html +++ /dev/null @@ -1,41 +0,0 @@ -<head> -<title>UK TeX FAQ -- question label write</title> -</head><body> -<h3>Writing (text) files from TeX</h3> -<p/>TeX allows you to write to output files from within your document. -The facility is handy in many circumstances, but it is vital for -several of the things LaTeX (and indeed almost any higher-level -TeX-based macro package) does for you. -<p/>The basic uses of writing to an external file are “obvious” — -remembering titles of sections for a table of contents, remembering -label names and corresponding section or figure numbers, all for a -later run of your document. However, the “non-obvious” thing is -easy to forget: that page numbers, in TeX, are slippery beasts, and -have to be captured with some care. The trick is that <code>\</code><code>write</code> -operations are only executed as the page is sent to the DVI -or PDF file. Thus, if you arrange that your page-number macro -(<code>\</code><code>thepage</code>, in LaTeX) is not expanded until the page is -written, then the number written is correct, since that time is where -TeX guarantees the page number tallies with the page being sent -out. -<p/>Now, there are times when you want to write something straight away: -for example, to interact with the user. TeX captures that -requirement, too, with the primitive <code>\</code><code>immediate</code>: -<blockquote> -<pre> -\immediate\write\terminal{I'm waiting...} -</pre> -</blockquote><p> -writes a “computer-irritates-user” message, to the terminal. -<p/>Which brings us to the reason for that <code>\</code><code>terminal</code>. TeX can -“<code>\</code><code>write</code>” up to 16 streams simultaneously, and that argument to -<code>\</code><code>write</code> says which is to be used. Macro packages provide the -means of allocating streams for your use: Plain TeX provides a macro -<code>\</code><code>newwrite</code><code>\</code><code>streamname</code>, which sets <code>\</code><code>streamname</code> as -the stream number. In fact, <code>\</code><code>terminal</code> (or its equivalent) is the -first output stream ever set up (in most macro packages): it is never -attached to a file, and if TeX is asked to write to <em>any</em> -stream that isn’t attached to a file it will send the output to the -terminal (and the log). -<p/><p>This question on the Web: <a href="http://www.tex.ac.uk/cgi-bin/texfaq2html?label=write">http://www.tex.ac.uk/cgi-bin/texfaq2html?label=write</a> -</body> |