c++ - Adding a common header file to all existing source and header through Eclipse -

In Eclipse IDE (C ++), how can I add a generic header file to all existing source and header files? I have a generic header file called "normal H". This file needs to be included in all the header files (.h) with all the source files (.h). Instead of manually adding "header.h" to #, how can I do this once through eclipse? My title is "header.h"

  #ifndef HEADER_H #define HEADER_H .... #endif  

I basically seek a short cut Avoid manual work. Actually, this is part of a comprehensive exercise where I would like to change all the study:; Seat with mout (say) where myout is a class of my own IISOSTream and myISTream is subclass from IOSTream. Potentially other people who open each file manually and ...