Go Channels

We all love to put go before functions to make them concurrent, but do we know how to control, share data in between go-routines? Today we will take a deep dive into channels and it’s working.

There are two types of channels: Buffered channel and Unbuffered channel.

A Buffered channel has the capacity to hold one or more values before they are received so they are used to perform asynchronous communication.a

Un-buffered channels don’t have any capacity that’s why they are used to perform synchronous communication between go-routines. It guarantees that the exchange between two go-routine is performed at the instant the send and receive take place. When we create a channel, channels have these properties within.

Let’s create a channel first, that’s simple.

Here’s how we pass data to a go-routine through the channel. What will be the output?

output: 10 is the data from channel

How? We are passing data in the function in the line next to the go func_name(c) then how this go-routine is getting data from the c <- 10

To understand this we have to dig deeper into the internal working of channels.

Let’s break the whole code execution into steps and see what's going on more clearly.

1: We declared a function func_name() which will print the data of the channel c chan int

2: We declare the main function

3: We now created a channel c:= make(chan int)

4: Now we passed the channel to the func_name(c) go-routine. but go-routine is blocked as of now, due to no data in the channel.

5: What happened is, we have two go-routines now. main and func_name

6: We are putting data to channel c <- 10 , this blocked our main go-routine and waiting for func_name to read the data. Now we have pushed data to our channel, the go scheduler now schedules func_name go-routine and it will read and print the value, now the execution of func_name is over.

7: Now the main go-routine unblocks and completes execution.

Hope you now have a clear idea of how channels work.

That’s all for this one. I will be writing some more about channels in my next article.

Thank you for reading.