package main import ( "fmt" "launchpad.net.gnuflag" ) func main() { fs := flag.NewFlagSet("myapp", flag.ExitOnError) var port int fs.IntVar(&port, "port", 8080, "HTTP server port") fs.Parse(os.Args[1:]) fmt.Printf("Starting server on port %d\n", port) // start server on the specified port }
package main import ( "fmt" "launchpad.net.gnuflag" ) func main() { fs := flag.NewFlagSet("myapp", flag.ExitOnError) var port int fs.IntVar(&port, "port", 8080, "HTTP server port") fs.IntVar(&port, "p", 8080, "HTTP server port (shorthand)") fs.Parse(os.Args[1:]) fmt.Printf("Starting server on port %d\n", port) // start server on the specified port }This example is similar to the first one, but we have defined a shorthand flag "-p" for the "port" flag. This allows the user to specify the port using "-p 8080" instead of "--port 8080". In conclusion, Launchpad.net.gnuflag is a package library in Go that provides a FlagSet struct and variable types to define and parse command line flags and arguments. It is useful for creating command line interfaces for Go programs.