Go language notes (4) go common management commands

Introduce

stay Go In language , Many of our operations are through go Order to proceed , For example, we need to implement go File compilation , You need to use go build command , except build Besides the command , There are also many commonly used commands , This time we will make a unified introduction , Have an understanding of common commands , In this way, we can more easily develop our Go Procedure .

Secondary title

go version：  obtain Go edition  
go env:  see Go environment variable  
go help：  see Go Help order  
go get：  Get remote package （ It needs to be installed in advance git or hg） 
go build：  Compile and generate executable programs  
go run：  Run the program directly 
 go fmt：  Format source code  
 go install：  Compile the package file and the whole program  
 go test： go Unit test commands provided by native  
 go clean：  Remove the files compiled and generated in the current source package and the associated source package  
 go tool：  upgrade Go version , Fix old code  
 godoc -http:80： Open a local 80 Port of web file  
 gdb  Executable name ： debugging Go Compiled file 

Use format ：

go command [arguments]``` ## go bulid go build , It can start compilation , Compile our package and related dependencies into   An executable file  .  If it is main package , perform go build after , An executable file will be generated in the current directory .  Example ： ```go
//  Compile the current directory as an executable  
go build 
//  Compile the current directory as an executable 
 go build . 
 //  compile hello.go The file is an executable  
 go build hello.g

If go bulid Report errors

/usr/lib/go-1.10/pkg/tool/linux_amd64/link: running gcc failed: exit status 1 
/tmp/go-link-008006128/000026.o: In function _cgo_05dc84caff82_Cfunc_sysconf': /tmp/go-build/cgo-gcc-prolog:32: multiple definition of_cgo_05dc84caff82_Cfunc_sysconf’ /tmp/go-link-008006128/000024.o:/tmp/go-build/cgo-gcc-prolog:32: first defined here collect2: error: ld returned 1 exit status

resolvent ：

linux: export CGO_ENABLED=0 
windows : cmd: set CGO_ENABLED=0 
windows ： powershell:$env:CGO_ENABLED=0

go run

go bulid Compile first , Then we need two steps to execute the executable file to execute our program
go run This command is the command that can combine these two steps into one step , Save us the time of entering

Command format ：

```go
go run  file name .go

Example ：

go run main.go

go install

go install Command and go bulid Commands are similar to those used to generate project executables , But it compiles , Install the generated executable file or library into the corresponding directory , For use .

 Install the executable to : $GOPATH/bin/
 Referential libraries installed to ： $GOPATH/pkg/
 Be careful ：  It's not turned on go mod when , You need to configure... To use the above command GOPATH, Otherwise it will be reported ：no install location.

go get

go get It is used to get the package in the remote warehouse , You must configure... Before using this command GOPATH, And according to different source websites , Also install different version management tools , For instance from github Upper use go get Additional installation required git.

go get In essence, it can be understood as through source code tools clone After code , Yes go install.

Command format ：
Download package ： add to -u Parameters can automatically update packages and dependencies

go get github.com/**/**

Use the installed package

import "github.com/****/****"

If the download is slow , Remember to configure goproxy

//  Set up module management model  
$ go env -w GO111MODULE=on 
// Set download source  
$ go env -w GOPR

go fmt

go fmt Command can format code files
Use go fmt command , It's actually called gofmt, And you need parameters -w, Otherwise, the formatting result will not be written to the file

// Command format ：
go fmt -w  file name .go
// Example ： Format the entire project 
gofmt -w -l src
// Common parameters ：
-l：  Those files that need to be formatted  
-w：  Write the rewritten content directly into the file , Instead of printing as a result to standard output . 
-r：  Add shapes like "a[b:len(a)] -> a[b:]" The rewriting rules of , It is convenient for us to make batch replacement  
-s：  Simplify the code in the file  
-d：  Displays the before and after formatting diff Instead of writing to a file , The default is false 
-e：  Print syntax errors to standard output . Without this parameter, only the front of different lines will be printed 10 A mistake .

go tool

go tool There were a lot of orders , There are mainly 2 individual , namely fix and vet：

	go tool fix .： Used to fix the old version of the code to the new version  
	go tool vet directory|files： Analyze whether the code of the current directory is correct