Book Image

Go Systems Programming

Book Image

Go Systems Programming

Overview of this book

Go is the new systems programming language for Linux and Unix systems. It is also the language in which some of the most prominent cloud-level systems have been written, such as Docker. Where C programmers used to rule, Go programmers are in demand to write highly optimized systems programming code. Created by some of the original designers of C and Unix, Go expands the systems programmers toolkit and adds a mature, clear programming language. Traditional system applications become easier to write since pointers are not relevant and garbage collection has taken away the most problematic area for low-level systems code: memory management. This book opens up the world of high-performance Unix system applications to the beginning Go programmer. It does not get stuck on single systems or even system types, but tries to expand the original teachings from Unix system level programming to all types of servers, the cloud, and the web.
Table of Contents (13 chapters)

Nil channels

This section will talk about nil channels, which are a special sort of channel that will always block. The name of the program will be nilChannel.go and will be presented in four parts.

The first part of the program contains the expected preamble:

package main 
 
import ( 
   "fmt" 
   "math/rand" 
   "time" 
) 

The second portion contains the implementation of the addIntegers() function:

func addIntegers(c chan int) { 
   sum := 0 
   t := time.NewTimer(time.Second) 
 
   for { 
         select { 
         case input := <-c: 
               sum = sum + input 
         case <-t.C: 
               c = nil 
               fmt.Println(sum) 
         } 
   } 
} 

The addIntegers() function stops after the time defined in the time.NewTimer() function passes and will go to the relevant branch of the case statement. There, it makes c a...