package main import ( "flag" ) var ( from, to string limit, offset int64 ) func init() { flag.StringVar(&from, "from", "", "file to read from") flag.StringVar(&to, "to", "", "file to write to") flag.Int64Var(&limit, "limit", 0, "limit of bytes to copy") flag.Int64Var(&offset, "offset", 0, "offset in input file") } func main() { flag.Parse() // Place your code here }