## Making Device Nodes Almost every device in the kernel has a corresponding node entry in the `/dev` directory. These nodes look like regular files, but are actually special entries into the kernel which programs use to access the device. The shell script `/dev/MAKEDEV`, which is executed when you first install the operating system, creates nearly all of the device nodes supported. However, it does not create all of them, so when you add support for a new device, it pays to make sure that the appropriate entries are in this directory, and if not, add them. Here is a simple example: Suppose you add the IDE CD-ROM support to the kernel. The line to add is: device acd0 This means that you should look for some entries that start with `acd0` in the `/dev` directory, possibly followed by a letter, such as `c`, or preceded by the letter `r`, which means a raw device. It turns out that those files are not there, so you must change to the `/dev` directory and type: # sh MAKEDEV acd0 When this script finishes, you will find that there are now `acd0c` and `racd0c` entries in `/dev` so you know that it executed correctly. For sound cards, the following command creates the appropriate entries: # sh MAKEDEV snd0 **Note:** When creating device nodes for devices such as sound cards, if other people have access to your machine, it may be desirable to protect the devices from outside access by adding them to the `/etc/fbtab` file. See [fbtab(5)](http://leaf.dragonflybsd.org/cgi/web-man?command#fbtab§ion5) for more information. Follow this simple procedure for any other non-`GENERIC` devices which do not have entries. **Note:** All SCSI controllers use the same set of `/dev` entries, so you do not need to create these. Also, network cards and SLIP/PPP pseudo-devices do not have entries in `/dev` at all, so you do not have to worry about these either.