Linux operator(often adding)

For myself to view:

1.mount -t vboxsf E_DRIVE /mnt/shared

2.tar xvzf arm-linux-gcc....tgz

3.Add PATH

　　export PATH=$PATH:/work/tools/...
 　　It is just for once.

　　We can edit:

　　#gedit /root/.bashrc

　　add:   export PATH=$PATH:/work/tools/...

4.