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diff --git a/Documentation/DocBook/procfs_example.c b/Documentation/DocBook/procfs_example.c
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+/*
+ * procfs_example.c: an example proc interface
+ *
+ * Copyright (C) 2001, Erik Mouw (J.A.K.Mouw@its.tudelft.nl)
+ *
+ * This file accompanies the procfs-guide in the Linux kernel
+ * source. Its main use is to demonstrate the concepts and
+ * functions described in the guide.
+ *
+ * This software has been developed while working on the LART
+ * computing board (http://www.lart.tudelft.nl/), which is
+ * sponsored by the Mobile Multi-media Communications
+ * (http://www.mmc.tudelft.nl/) and Ubiquitous Communications 
+ * (http://www.ubicom.tudelft.nl/) projects.
+ *
+ * The author can be reached at:
+ *
+ *  Erik Mouw
+ *  Information and Communication Theory Group
+ *  Faculty of Information Technology and Systems
+ *  Delft University of Technology
+ *  P.O. Box 5031
+ *  2600 GA Delft
+ *  The Netherlands
+ *
+ *
+ * This program is free software; you can redistribute
+ * it and/or modify it under the terms of the GNU General
+ * Public License as published by the Free Software
+ * Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * This program is distributed in the hope that it will be
+ * useful, but WITHOUT ANY WARRANTY; without even the implied
+ * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+ * PURPOSE.  See the GNU General Public License for more
+ * details.
+ * 
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place,
+ * Suite 330, Boston, MA  02111-1307  USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/proc_fs.h>
+#include <linux/jiffies.h>
+#include <asm/uaccess.h>
+
+
+#define MODULE_VERS "1.0"
+#define MODULE_NAME "procfs_example"
+
+#define FOOBAR_LEN 8
+
+struct fb_data_t {
+        char name[FOOBAR_LEN + 1];
+        char value[FOOBAR_LEN + 1];
+};
+
+
+static struct proc_dir_entry *example_dir, *foo_file,
+        *bar_file, *jiffies_file, *symlink;
+
+
+struct fb_data_t foo_data, bar_data;
+
+
+static int proc_read_jiffies(char *page, char **start,
+                             off_t off, int count,
+                             int *eof, void *data)
+{
+        int len;
+
+        len = sprintf(page, "jiffies = %ld\n",
+                      jiffies);
+
+        return len;
+}
+
+
+static int proc_read_foobar(char *page, char **start,
+                            off_t off, int count, 
+                            int *eof, void *data)
+{
+        int len;
+        struct fb_data_t *fb_data = (struct fb_data_t *)data;
+
+        /* DON'T DO THAT - buffer overruns are bad */
+        len = sprintf(page, "%s = '%s'\n", 
+                      fb_data->name, fb_data->value);
+
+        return len;
+}
+
+
+static int proc_write_foobar(struct file *file,
+                             const char *buffer,
+                             unsigned long count, 
+                             void *data)
+{
+        int len;
+        struct fb_data_t *fb_data = (struct fb_data_t *)data;
+
+        if(count > FOOBAR_LEN)
+                len = FOOBAR_LEN;
+        else
+                len = count;
+
+        if(copy_from_user(fb_data->value, buffer, len))
+                return -EFAULT;
+
+        fb_data->value[len] = '\0';
+
+        return len;
+}
+
+
+static int __init init_procfs_example(void)
+{
+        int rv = 0;
+
+        /* create directory */
+        example_dir = proc_mkdir(MODULE_NAME, NULL);
+        if(example_dir == NULL) {
+                rv = -ENOMEM;
+                goto out;
+        }
+        
+        example_dir->owner = THIS_MODULE;
+        
+        /* create jiffies using convenience function */
+        jiffies_file = create_proc_read_entry("jiffies", 
+                                              0444, example_dir, 
+                                              proc_read_jiffies,
+                                              NULL);
+        if(jiffies_file == NULL) {
+                rv  = -ENOMEM;
+                goto no_jiffies;
+        }
+
+        jiffies_file->owner = THIS_MODULE;
+
+        /* create foo and bar files using same callback
+         * functions 
+         */
+        foo_file = create_proc_entry("foo", 0644, example_dir);
+        if(foo_file == NULL) {
+                rv = -ENOMEM;
+                goto no_foo;
+        }
+
+        strcpy(foo_data.name, "foo");
+        strcpy(foo_data.value, "foo");
+        foo_file->data = &foo_data;
+        foo_file->read_proc = proc_read_foobar;
+        foo_file->write_proc = proc_write_foobar;
+        foo_file->owner = THIS_MODULE;
+                
+        bar_file = create_proc_entry("bar", 0644, example_dir);
+        if(bar_file == NULL) {
+                rv = -ENOMEM;
+                goto no_bar;
+        }
+
+        strcpy(bar_data.name, "bar");
+        strcpy(bar_data.value, "bar");
+        bar_file->data = &bar_data;
+        bar_file->read_proc = proc_read_foobar;
+        bar_file->write_proc = proc_write_foobar;
+        bar_file->owner = THIS_MODULE;
+                
+        /* create symlink */
+        symlink = proc_symlink("jiffies_too", example_dir, 
+                               "jiffies");
+        if(symlink == NULL) {
+                rv = -ENOMEM;
+                goto no_symlink;
+        }
+
+        symlink->owner = THIS_MODULE;
+
+        /* everything OK */
+        printk(KERN_INFO "%s %s initialised\n",
+               MODULE_NAME, MODULE_VERS);
+        return 0;
+
+no_symlink:
+        remove_proc_entry("tty", example_dir);
+no_tty:
+        remove_proc_entry("bar", example_dir);
+no_bar:
+        remove_proc_entry("foo", example_dir);
+no_foo:
+        remove_proc_entry("jiffies", example_dir);
+no_jiffies:                           
+        remove_proc_entry(MODULE_NAME, NULL);
+out:
+        return rv;
+}
+
+
+static void __exit cleanup_procfs_example(void)
+{
+        remove_proc_entry("jiffies_too", example_dir);
+        remove_proc_entry("tty", example_dir);
+        remove_proc_entry("bar", example_dir);
+        remove_proc_entry("foo", example_dir);
+        remove_proc_entry("jiffies", example_dir);
+        remove_proc_entry(MODULE_NAME, NULL);
+
+        printk(KERN_INFO "%s %s removed\n",
+               MODULE_NAME, MODULE_VERS);
+}
+
+
+module_init(init_procfs_example);
+module_exit(cleanup_procfs_example);
+
+MODULE_AUTHOR("Erik Mouw");
+MODULE_DESCRIPTION("procfs examples");