Following go conventions.

'go lint' is your friend

https://github.com/golang/lint

Effective Go: https://golang.org/doc/effective_go.html

helloweb.go:49:2: don't use underscores in Go names; var bind_ip should be bindIP
helloweb.go:50:2: don't use underscores in Go names; var bind_port should be bindPort
helloweb.go:51:2: don't use underscores in Go names; var bind_addr should be bindAddr