A network request can block while a feed reader waits for a response. Prefix a function call with `go` to run it as a goroutine, letting the rest of the program continue. The Go runtime schedules goroutines across OS threads; no thread pool or executor needs configuring. section 9.1 section 1.4.1
Listing 9.3 main.go: Fetching data via a goroutine
package main
...
func main() {
fp := gofeed.NewParser()
go func(url string) { #1
feed, _ := fp.ParseURL(url) #2
fmt.Println(feed.Title)
}("https://rss.nytimes.com/services/xml/rss/nyt/World.xml") #3
}
An anonymous function fetches and prints an RSS feed title. The `go` keyword starts the function call concurrently with `main`. section 9.1
Starting a goroutine does not keep the program alive. If `main` returns before the fetch finishes, the program exits and the title may never print. A fixed `time.Sleep` can make the example appear to work, but guessing a network request’s duration is not reliable synchronization. section 9.1
Listing 9.5 main.go: A second goroutine
func main() {
go printFeedTitle("https://rss.nytimes.com/services/xml/rss/nyt/World.xml")
go printFeedTitle("https://feeds.bbci.co.uk/news/
rss.xml") #1
fmt.Println("waiting....")
time.Sleep(15 * time.Second)
fmt.Println("stopped.")
}
Two calls to `printFeedTitle` start separate goroutines for separate news feeds. They still need a reliable way to finish before `main` returns. section 9.1
