to delete all the io pins in a design and load a new io file

hi, 

i am looking for the deletion of all the IO pins in my current design and loading a new IO file which has the correct pin location. Need the user guide or the command for this. I tried using deleteIoInstance - with which we will have to give a string in order to delete all the IO pins. 

Please also point me to the INnnovus user guide.

Regards

Sar