I’ve been exploring channels and playing around with some basic

Question

I’ve been exploring channels and playing around with some basic

edge cases. I understand for a successful transaction to occur in a channel, A sender and a receiver must be available, for a given “message”.

Why does the following operation not result in a deadlock?

package main

func main() {
messages := make(chan string)

// A go routine that sends to a channel
go func() {
messages <- "I am sending a message."
}()

// Main routine has no receiver.
// No compilation or runtime error.
// Why doesn't it deadlock?
}

0

09.07.2021

11 ответов

23 просмотра

jeffotoni

so if I understand correctly deadlock will only occur if you try to access the channel without goroutines because the channel has no buffer.

0

09.07.2021

jeffotoni

jeffotoni
so if I understand correctly deadlock will only oc...

package main func main() { messages := make(chan string) // A go routine that sends to a channel //go func() { messages <- "I am sending a message." //}() }

0

09.07.2021

jeffotoni

jeffotoni
package main func main() { messages := make(cha...

if you make a buffered channel it will work messages := make(chan string, 1)

0

09.07.2021

Thirteen

jeffotoni
package main func main() { messages := make(cha...

main would have exited by then

0

09.07.2021

Justin K Автор вопроса

jeffotoni
if you make a buffered channel it will work messag...

Yes, I did play with buffer sizes. Unless I misunderstood, I read somewhere that buffer channels have their time and place. To limit their use and rather keep the code “tightly coupled” for each successful channel transaction to occur (or something). Is that a valid point?

0

09.07.2021

jeffotoni

Justin K
Yes, I did play with buffer sizes. Unless I misund...

When using buffering there is no need to use goroutine for example. When we don't have a buffer on the channel, the use of goroutines is mandatory.

0

09.07.2021

Justin K Автор вопроса

jeffotoni
When using buffering there is no need to use gorou...

Thanks, Yes, I understand that bit but the point I wrote just earlier, is that a valid consideration at all? That to use buffer only if the solution really requires of the channel to hold a few messages?

0

09.07.2021

jeffotoni

Justin K
Thanks, Yes, I understand that bit but the point I...

Yes, adaptation by need and problems we know the amount to be shared.

0

09.07.2021

Justin K Автор вопроса

jeffotoni
Yes, adaptation by need and problems we know the a...

Yes agree!

0

09.07.2021