go 基础详解---环境变量以及命令行详解

go --help

Go is a tool for managing Go source code.

Usage:

        go <command> [arguments]

The commands are:

        bug         start a bug report
        build       compile packages and dependencies
        clean       remove object files and cached files
        doc         show documentation for package or symbol
        env         print Go environment information
        fix         update packages to use new APIs
        fmt         gofmt (reformat) package sources
        generate    generate Go files by processing source
        get         add dependencies to current module and install them
        install     compile and install packages and dependencies
        list        list packages or modules
        mod         module maintenance
        work        workspace maintenance
        run         compile and run Go program
        test        test packages
        tool        run specified go tool
        version     print Go version
        vet         report likely mistakes in packages

Use "go help " for more information about a command.

Additional help topics:

        buildconstraint build constraints
        buildmode       build modes
        c               calling between Go and C
        cache           build and test caching
        environment     environment variables
        filetype        file types
        go.mod          the go.mod file
        gopath          GOPATH environment variable
        gopath-get      legacy GOPATH go get
        goproxy         module proxy protocol
        importpath      import path syntax
        modules         modules, module versions, and more
        module-get      module-aware go get
        module-auth     module authentication using go.sum
        packages        package lists and patterns
        private         configuration for downloading non-public code
        testflag        testing flags
        testfunc        testing functions
        vcs             controlling version control with GOVCS

Use "go help " for more information about that topic.

go version

C:\Users\love1>go version
go version go1.19.2 windows/amd64

go env

C:\Users\love1>go  help env
usage: go env [-json] [-u] [-w] [var ...]

Env prints Go environment information.

By default env prints information as a shell script
(on Windows, a batch file). If one or more variable
names is given as arguments, env prints the value of
each named variable on its own line.

The -json flag prints the environment in JSON format
instead of as a shell script.

The -u flag requires one or more arguments and unsets
the default setting for the named environment variables,
if one has been set with 'go env -w'.

The -w flag requires one or more arguments of the
form NAME=VALUE and changes the default settings
of the named environment variables to the given values.

For more about environment variables, see 'go help environment'.

打印某个具体的环境变量值

C:\Users\love1>go env GOROOT
C:\Program Files\Go

修改某个变量的值 go env -w GO111MODULE=off (是永久修改的)

go env -u 变量名1、变更名2… 恢复这些环境变量的默认配置