This file is part of eRCaGuy_hello_world: https://github.com/ElectricRCAircraftGuy/eRCaGuy_hello_world

Go (Golang)

References

1. Getting started with Go
   1. https://learnxinyminutes.com/docs/go/
   2. Tutorial: Get started with Go: https://go.dev/doc/tutorial/getting-started
   3. https://go.dev/ - official Go website
   4. https://www.tutorialspoint.com/go/index.htm
2. [my answer] How to specify an output name or path when building in Go (golang)
3. [my answer] What's the appropriate Go shebang line?

Common commands, building, and help

Notes:

1. Go is a compiled language! It is NOT an interpreted or "scripted" or "script-based" language! go run actually compiles and runs in one command.
   1. See: Is Google's Golang an interpreter or compiler?

See especially:

1. [my answer] How to specify an output name or path when building in Go (golang)

# print main help menu
go help
go --help  # same as above

# get help on a specific command
go help <command>  

# Ex: get help on the `go run` command, which both compiles and runs a go program in one cmd
go help run
# Or get help on the build command
go help build

# very short help output
go build --help

# Build `hello_world.go` into an executable named "hello_world" inside your **current
# directory** (NOT necessarily inside the directory where your .go file being built is
# located).
go build hello_world.go 

From my answer above:

# ---------------------
# general formats
# ---------------------

# 1. build input file "filename.go" into an executable
# named "executable_filename" within the directory you are currently `cd`ed
# into
go build -o executable_filename filename.go

# 2. build input file "filename.go" into an executable at
# path "output_dir/filename"; this automatically creates directory "output_dir"
# if it does not already exist
go build -o output_dir/ filename.go

# 3. build input file "filename.go" into an executable at
# path "output_dir/whatever"; this automatically creates directory "output_dir"
# if it does not already exist
go build -o output_dir/whatever filename.go

# ---------------------
# examples
# ---------------------

# create executable "whatever" from "hello_world.go"
go build -o whatever hello_world.go

# make directory "bin" and create executable "bin/hello_world"
# from "hello_world.go"
go build -o bin/ hello_world.go

# make directory "bin" and create executable "bin/whatever"
# from "hello_world.go"
go build -o bin/whatever hello_world.go

# see the short help menu for `go run`
go run --help

# see the long help menu for `go run`
go help run

# build and run this file all at once!
go run hello_world.go

To install Go on Ubuntu:

See: https://go.dev/doc/install

# prepare a download directory
cd ~/Downloads
mkdir Install_files/Go
cd Install_files/Go

# Download the installation file
# Note: update the URL and file version below with the latest one from here:
# https://go.dev/doc/install
wget https://go.dev/dl/go1.17.8.linux-amd64.tar.gz

# MANUALLY BACK UP THE OLD INSTALLATION DATA AT THIS POINT, IF DESIRED!

# remove old installation, if there was one
sudo rm -rf /usr/local/go
# extract new installation to "/usr/local/go"
sudo tar -C /usr/local -xzf go1.17.8.linux-amd64.tar.gz

# add "/usr/local/go/bin" to your PATH to allow you to run the `go` executable
echo '# add golang executable path to PATH variable' >> ~/.bashrc
echo 'export PATH=$PATH:/usr/local/go/bin' >> ~/.bashrc
# re-source your ~/.bashrc file to bring in that PATH variable change to your current terminal
. ~/.bashrc

# Verify that you have `go` installed by checking its version and ensuring it matches the version
# of the file you downloaded above. Sample output:
#       go version go1.17.8 linux/amd64
go version

TODO

1. finish the hello_world.go demo

   Done as of hash 48367d7bce3b22e86d567f5d361abef63b574b25 or so.

2. Figure out and add a shebang line which will compile and run go

   1. Google search for "hashbang for go"
   2. What's the appropriate Go shebang line?
   3. *****+ https://unix.stackexchange.com/a/162535/114401
   4. Run C or C++ file as a script

   Done as of hash 48367d7bce3b22e86d567f5d361abef63b574b25 or so.