# Plain TeX: running header with section name

I want to create a TeX document with sections and a running header containing the name of the current section. I know I can use `\mark{}` to mark the section headings and then use `\topmark` or `\firstmark` to show the section name in my header. The problem is that neither `\topmark` nor `\firstmark` do what I want (they're actually more suitable for typesetting dictionaries).

I would like the header to reflect the section the contents of which appear at the very top of the current page. In other words, I want to use mostly `\topmark`, but when a new section begins on the current page before any other text before it, I want to use `\firstmark` (or, alternatively, leave the header blank), because then `\topmark` refers to the previous section and thus is irrelevant. Any ideas on how I could do that?

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There's exactly this problem explained in the TeXbook, since TAOCP uses that kind of headers. The trick consists in issuing `\mark` twice, before and after the section title, if I remember correctly. –  egreg Jun 28 '11 at 16:58
On page 260, to be precise. –  Javier Bezos Jun 29 '11 at 14:12
@egreg Thanks, that helped. But there's one problem: on the first page, `\topmark` is still empty. Can I tell TeX to use `\firstmark` instead? –  ondra.cifka Jun 29 '11 at 17:27
Usually the first page has no headers. :) I suppose that `\ifnum\pageno=1 \firstmark\else\topmark\fi` can solve the issue. –  egreg Jun 29 '11 at 18:04

``````\ifnum\pageno=1 \firstmark\else\topmark\fi