title: Read only file system android (is /mnt not /system)
body: <p>Android device, I want to touch a file or dir in /mnt, it say &quot;Read only file system&quot;, I don't know how to do. i try fix it with that fix /system, but it no work.</p>
  <pre><code>root@android:/ # ls -l
  .....
  drwxrwxr-x root     system            2011-01-01 11:33 mnt
  .....
  root@android:/ # 
  root@android:/ # mkdir /mnt/test
  mkdir failed for /mnt/test, Read-only file system
  255|root@android:/ # 
  
  
  root@android:/ # mount -o remount,rw /mnt
  Usage: mount [-r] [-w] [-o options] [-t type] device directory
  1|root@android:/ # 
  </code></pre>
  <p>can't fix it as /system.
  how can i do it?</p>
  <pre><code>root@android:/ # id
  uid=0(root) gid=0(root)
  root@android:/ # 
  </code></pre>
  <p>But i can make directory in /mnt/xxx/, like this:</p>
  <pre><code>root@android:/ # mkdir /mnt/usb_storage/test                                   
  root@android:/ # ls /mnt/usb_storage/test/                                     
  root@android:/ # ls /mnt/usb_storage/                                          
  test
  root@android:/ # 
  </code></pre>
  <hr />
  <p><strong>And</strong></p>
  <p>i fond difference between /mnt and /mnt/usb_storage in init.rc</p>
  <p>look /mnt:</p>
  <pre><code># create mountpoints                                                            
      mkdir /mnt 0775 root system
  </code></pre>
  <p>look /mnt/usb_storage:</p>
  <pre><code># Directory for multi usb storage                                       
  mkdir /mnt/usb_storage 0700 root system                                 
  mount tmpfs tmpfs /mnt/usb_storage mode=0755 gid=1000 
  </code></pre>
  <p>Yes!I fix it!</p>
  <p>create mountpoints</p>
  <p>mkdir /mnt 0775 root system</p>
  <p>add <strong>mount tmpfs tmpfs /mnt/ mode=0755 gid=1000</strong></p>
  <p><strong>now i can touch file or make directory in /mnt</strong></p>
  <pre><code>root@android:/mnt # mkdir /mnt/test
  root@android:/mnt # ls -l /mnt/                                                
  ....
  drwxrwxrwx root     root              2011-01-01 11:04 test
  drwxrwxrwt root     system            2011-01-01 11:00 usb_storage
  root@android:/mnt # 
  </code></pre>
  <hr />
  <h3>Resolved</h3>
  <p>ramdisk rootfs is read only.</p>
  <pre><code>mount -o remount,rw /
  </code></pre>