BLOCK diff_file								                              
  Utility to update text files with the differences in a diff_file,          
  the utility replaces a block of lines with another block of lines          
                                                                             
   The format of the diff_file:                                              
                                                                             
     <block> file1.ext                                                     
     <Line1 old block                                                        
     <Line2 old block                                                        
     <...                                                                    
     <Line<n> old block                                                      
     >Line1 new block                                                        
     >Line2 new block                                                        
     >...                                                                    
     <Line<n> new block                                                      
                                                                             
     <plocinf> file2.ext                                                     
      ...