chore: new draft thoughts

src/posts/drafts/cross-platform-development.md

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+---
+title: Cross platform development 101
+tags:
+ - c/c++
+ - build-tools
+ - cross-platform development
+---
+One thing I love about the web platform is that its cross-platform compatibility. Many (most) common operating system comes with a browser preinstalled. You can take a piece of HTML, CSS and JavaScript and it will work (mostly) everywhere.
+
+How does it work?
+
+You can create a program and compile it everywhere. Take this helloworld.c for example:
+
+```c
+#include <stdio.h>
+
+int main(int argc, char *argv[]) {
+  printf("Hello World!\n");
+  return 0;
+}
+```
+
+This program will compile on pretty much every platform where standard C is available.
+The build step may differ a bit from platform to platform:
+
+```sh
+# On GNU systems such as GNU/Linux or MINGW (Minimalist GNU for Windows):
+gcc -o hello helloworld.c
+
+# On a Mac:
+clang -o hello helloworld.c
+
+# On FreeDOS or DOSBox, using OpenWatcom 2.0:
+wcc helloworld.c
+wlink name hello.exe file { hello.obj }
+
+# On FreeDOS or DOSBox, using DJGPP:
+djgpp -o hello.exe helloworld.c
+```
+
+As you can already see, the build process slightly different from platform to platform. But things can be automated. The gcc command will also work on a mac as it is linked to clang. Also, the clang compiler command line interface is compatible with gcc.
+
+## Makefiles
+
+As projects grow larger and pull in multiple dependencies, the build process can get more complex.
+
+Makefiles come to the rescue. You can define several build steps in a Makefile.
+The syntax of a Makefile is as follow:
+
+```sh
+hello:
+  echo Hello Lea!
+
+compile:
+  touch output.txt
+
+clean:
+  rm output.txt
+```
+
+When running `make`, you can see `echo Hello Lea!` is run.  By default, only the first step is run.
+
+The Makefile above has also an additional build step `compile` to generate some kind of output (in this case, a 0-byte file named `output.txt` is generated).
+
+Another common build step is one for cleaning up: `make clean` cleans up the folder, so you can create a clean build afterwards.
+
+In-depth tutorial on Makefiles: <https://opensource.com/article/18/8/what-how-makefile>
+
+### A Makefile for Watcom C
+
+```txt
+obj = hello.obj
+bin = hello.exe
+
+CC = wcc
+CFLAGS = -zq
+LD = wlink
+
+$(bin): $(obj)
+        $(LD) name $(bin) file { $(obj) }
+
+.c.obj:
+        $(CC) -fo=$@ $(CFLAGS) $<
+
+clean: .symbolic
+        del *.obj
+        del $(bin)
+```
+
+When building with OpenWatcom C and MS-DOS, there are also differences in the Makefile. For example, `del` is used to delete files in DOS while `rm` is used to delete file in a UNIX-like OS. Also, the command line interface is different.
+
+## OWCC to the rescue
+
+OpenWatcom v2 comes with `owcc` which has a command-line interface which is compatible to `gcc`.
+
+## GNU autotools
+
+GNU systems such with GNU/Linux or Mingw come with build tools which can create platform
+
+In depth resources:
+
+- [Tutorial](https://opensource.com/article/19/7/introduction-gnu-autotools)
+- [GNU autoconf](https://www.gnu.org/savannah-checkouts/gnu/autoconf/manual/autoconf-2.72/autoconf.html)