Running TEX

Let's now typeset nasty.tex. Before starting TEX we need to make sure that the correct format will be used. All the available formats appear at the end of the TEX menu. Check this menu and make sure the Plain format is ticked; this is the format required by nasty.tex. (This check is not actually needed because the first line of nasty.tex contains ``%&Plain'' which forces to use the Plain format.) Choose ``TEX ...'' from the TEX menu and open nasty.tex. The window will be cleared, TEX will start up, load the Plain format, and begin reading the given input file. When it sees the unknown command, TEX will display a suitable error message, beep, and wait for you to type something. Note that a solid block cursor sits next to TEX's ``?'' prompt. This block cursor always appears when TEX is waiting for you to type something. The window should contain the following:


This is TeX, Version 3.14159 (no format preloaded)
**&Plain nasty.tex
(nasty.tex
! Undefined control sequence.
l.5 \xxx

? width .4em height .7em depth .15em


Chapter 6 in The TEXbook explains what you can do in such a situation. (Section [*] describes how you can type ``e'' to tell to switch to your editor and open the file containing the error, possibly with the error line selected.) In this case we can simply ignore the error and continue by hitting the Return key. Although nasty.tex is not very nice, you shouldn't see any more TEX errors. A 19-page DVI file called nasty.dvi should be created. Have a look at the second item in both the File and View menus. Whenever a new DVI file is created, its name will automatically appear in these items so you can quickly print or view the DVI file without going through the open-file dialog. The second item in the TEX menu has also been updated with the name of the most recent input file (nasty.tex in this case), so you can easily typeset the same file again by pressing Command-T. The file name also appears in the bottom item of the Edit menu so you can quickly switch back to your editor by pressing Command-E. supports background typesetting. At any time while TEX is running you can switch to another application and TEX will continue to run in the background. Whenever finishes a lengthy task in the background (like typesetting or printing), or if some sort of user interaction is required (say a TEX error occurs), then under System 6 or later you will be notified by a flashing icon in the menu bar. A diamond mark will also appear next to in the list of current applications. At the end of every TEX run, displays the time taken and the amount of memory allocated by TEX for its large arrays. The total number of bytes depends on the current TEX parameters. The values in the Default config file are suitable for small to medium-size documents. For some documents you might need to increase one or more TEX parameters; you'll know this is necessary if TEX quits with a ``capacity exceeded'' error; see section [*]. For very large documents, like a book or thesis, you will probably need to increase most of the parameters and create big formats; see section [*].