concurrency - Reusing a Go channel causes deadlock -


i'm new golang (whith java concurrency background). consider peace of code :

package main  import "fmt"  func sendenum(num int, c chan int) {     c <- num }  func main() {     c := make(chan int)     go sendenum(0, c)     x, y := <-c, <-c     fmt.println(x, y) }

when run code , error

fatal error: goroutines asleep - deadlock!  goroutine 1 [chan receive]: main.main()     /home/tarrsalah/src/go/src/github.com/tarrsalah/stackoverflow/chan_dead_lock.go:12 +0x90 exit status 2

i know, adding go sendenum(0, c) statement fix issue, ... but

when , where deadlock happened ?

after receives 0, main keeps on waiting on receiving end of c value arrive (to put in y variable), never will, goroutine running main 1 left live.

when add go sendenum(0, c), gets value on second channel receive, puts y variable, prints x , y out , program finishes succesfully.


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