### 18.1 How to Use Include Files

To include another file within a Texinfo file, write the `@include` command at the beginning of a line and follow it on the same line by the name of a file to be included. For example:

```@include buffers.texi
```

@-commands are expanded in file names. The one most likely to be useful is `@value` (see `@set @value`), and even then only in complicated situations.

An included file should simply be a segment of text that you expect to be included as is into the overall or outer Texinfo file; it should not contain the standard beginning and end parts of a Texinfo file. In particular, you should not start an included file with a line saying ‘\input texinfo’; if you do, that text is inserted into the output file literally. Likewise, you should not end an included file with a `@bye` command; nothing after `@bye` is formatted.

In the long-ago past, you were required to write an `@setfilename` line at the beginning of an included file, but no longer. Now, it does not matter whether you write such a line. If an `@setfilename` line exists in an included file, it is ignored.