關于chan的疑問
package?main
import?(
???"fmt"
)
func?main()?{
???ch?:=?make(chan?string)
???for?i?:=?0;?i?<=?5;?i++?{
??????go?printHelloWorld(i,?ch)
???}
???for?{
??????if?msg,ok?:=?<-ch;ok{
?????????fmt.Println(msg)
??????}else{
?????????break
??????}
???}
}
func?printHelloWorld(i?int,?ch?chan?string)?{
??????ch?<-?fmt.Sprintf("hello?world?%d\n",?i)
}老師：為什么我這段代碼輸出會有個??
fatal error: all goroutines are asleep - deadlock!
報錯呢？
2018-06-10
改成這樣就可以了：
2018-06-10
ch沒有關閉，一直在等待。
package?mainimport?( "fmt")func?main()?{ ch?:=?make(chan?string) for?i?:=?0;?i?<=?5;?i++?{ go?printHelloWorld(i,?ch) } for?i?:=?0;?i?<=?5;?i++?{ fmt.Println(<-ch) }}func?printHelloWorld(i?int,?ch?chan<-?string)?{ ch?<-?fmt.Sprintf("hello?world?%d\n",?i)}