#include <linux/module.h>
+/* Needed for procfs register functions */
#include <linux/proc_fs.h>
+/* Needed for using the seq_file infrastructure */
+#include <linux/seq_file.h>
MODULE_AUTHOR("Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>");
MODULE_LICENSE("GPL");
+/* write our message to the sequential file */
+static int hello_show(struct seq_file *file, void *data)
+{
+ seq_puts(file, "Hello, world!\n");
+ return 0;
+}
+
+/* use the single sequential file */
+static int hello_procfs_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, hello_show, NULL);
+}
+
+/* our file operations use the seq_file stuff to make it an easy task */
+static const struct file_operations hello_procfs_fops =
+{
+ .open = hello_procfs_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
static int hello_procfs_init(void)
{
+ /* create the proc entry and set its fops: there is a potential race
+ * here */
+ struct proc_dir_entry *entry;
+ entry = proc_create("hellop", 0666, NULL, &hello_procfs_fops);
return 0;
}
static void hello_procfs_exit(void)
{
+ /* remove our proc entry */
+ remove_proc_entry("hellop", NULL);
}
module_init(hello_procfs_init);