## Resources
- [What is a Makefile and how does it work?](https://opensource.com/article/18/8/what-how-makefile)
- [C++ Programming Tutorial 75 - Creating a Simple Makefile](https://youtu.be/6Gw1rNyTJWA)
- [makefiles: the problem](https://calmcode.io/makefiles/the-problem.html)
- [How To Manage Your Dotfiles With Make](https://youtu.be/aP8eggU2CaU)
- [How To Write a Makefile](https://youtu.be/TQ7SyYyKXhk)
- <https://www.gnu.org/software/make/manual/make.html>
## Installation on Windows
- Install from [Here](http://gnuwin32.sourceforge.net/packages/make.htm)
- Run `C:\MinGW\bin\mingw-get.exe` to install the Make tools
- Add `C:\MinGW\bin` to your `$PATH`
- make [[powershell]] alias of `mingw32-make.exe` to `make`
```powershell
New-Alias -Name make -Value mingw32-make.exe
```
## Inference rules
```bash
# ==================
# USING INFERENCE RULES
# ==================
# $@ = prod.txt (if out of date)
# $* = prod (its the target with the .extention removed)
#
lt; = dep.txt (aka its the first dependancy)
# .SUFFIXES appends these to suffixes used for inference rules
.SUFFIXES: .tmp .txt
all: tester.txt
# make a .txt file using a .tmp file
# lt; for the .tmp file
# $@ for the .txt file
# .inextension.outextension:
.tmp.txt:
cat lt; > $*
```
## Specifying dependency targets
```bash
final_target: sub_target final_target.c
Recipe_to_create_final_target
sub_target: sub_target.c
Recipe_to_create_sub_target
```
```bash
say_hello:
echo "Hello World"
```
- `say_hello:` == _The Target_
- _prerequisites_ or _dependencies_ follow the target
- `echo "Hello World"` == _The Recipe_
- The _target_, _prerequisites_, and _recipes_ together make a _rule_.
- **Suppress command** text and only show output with `@` like `@echo "hello world"`
```bash
say_hello:
@echo "Hello World"
generate:
@echo "Creating empty text files..."
touch file-{1..10}.txt
clean:
@echo "Cleaning up..."
rm *.txt
```
- This will only run the `say_hello` function because it's the default target ( the first thing )
- to hard code the default target, include this at beginning of file: `.DEFAULT_GOAL := generate`
- To instead run all targets the target `all` is used to call all other targets
```bash
all: say_hello generate
say_hello:
@echo "Hello World"
generate:
@echo "Creating empty text files..."
touch file-{1..10}.txt
clean:
@echo "Cleaning up..."
rm *.txt
```
## Variable aka Macros
> are like variable replacement in makefiles
```bash
# ==================
# USING VARIABLES (aka macros)
# ==================
# VARIABLENAME = VALUE OF VARIABLE
# they expand using the syntax $(VARIABLENAME)
TMP = tester1.txt
OUTPUT = tester2.txt
$(OUTPUT): $(TMP)
cat $(TMP) > $(OUTPUT)
$(TMP):
echo "this is a test" > $(TMP)
```