Raw Formatter Commands

Inside a region delineated by @iftex and @end iftex, you can embed some raw TeX commands. Info will ignore these commands since they are only in that part of the file which is seen by TeX. You can write the TeX commands as you would write them in a normal TeX file, except that you must replace the \ used by TeX with an @. For example, in the @titlepage section of a Texinfo file, you can use the TeX command @vskip to format the copyright page. (The @titlepage command causes Info to ignore the region automatically, as it does with the @iftex command.)

However, many features of plain TeX will not work, as they are overridden by Texinfo features.

You can enter plain TeX completely, and use \ in the TeX commands, by delineating a region with the @tex and @end tex commands. (The @tex command also causes Info to ignore the region, like the @iftex command.) The sole exception is that the @ character still introduces a command, so that @end tex can be recognized properly.

For example, here is a mathematical expression written in plain TeX:

     @tex
     $$ \chi^2 = \sum_{i=1}^N
              \left (y_i - (a + b x_i)
              \over \sigma_i\right)^2 $$
     @end tex
     

The output of this example will appear only in a printed manual. If you are reading this in Info, you will not see the equation that appears in the printed manual.

Analogously, you can use @ifhtml ... @end ifhtml to delimit a region to be included in HTML output only, and @html ... @end html for a region of raw HTML (again, except that @ is still the escape character, so the @end command can be recognized.)

Analogously, you can use @ifxml ... @end ifxml to delimit a region to be included in XML output only, and @xml ... @end xml for a region of raw XML (again, except that @ is still the escape character, so the @end command can be recognized.)