kernel_module_learn/lang_c/03_character_device

Additionnal informations

To test character device, your need create the device.

Step 1: Get major number of your module device

cat /proc/devices | grep flodev

Step 2: Create device (as root)

mknod /dev/[wanted name] -c <major_number> 0

Exemple (as root):

cat /proc/devices | grep flodev # => 236 flodev
mknod /dev/flodev0 c 236 0
echo "Salut" >> /dev/flodev0
dmesg | tail # =>
#   flodev - Ouverture du périphérique
#   flodev - Message reçu: Salut
#   flodev - Fermeture du périphérique
rm /dev/flodev0