Hi Monks!

I have a perl script to do some minor modification to content of large file. The problem is modification needed is at beginning of file. and since the file is quite huge (>2GB), it can sometimes take very long just to copy rest of remaining data. Is there any way to make it almost as fast as copying (say using cp command)? 

   
   while( data = read_data(fh) ) {
       if( data_to_modify(data) ) {
            out_fh->write(modified_data);
             last; # break out
       }
   }
   while( read(fh,buffer,buffer_size) ) { 
       out_fh->write(buffer);
   }

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In reply to Modifying small part of large file by pwagyi

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