README: Add instructions for MacOS

README.md

@@ -35,14 +35,29 @@ Building
 
 To build the standalone SDK and toolchain, you need a GNU/POSIX system
 (Linux, BSD, MacOSX, Windows with Cygwin) with the standard GNU development
-tools installed: gcc, binutils, flex, bison, etc. For Ubuntu 14.04
-run:
+tools installed: gcc, binutils, flex, bison, etc.
 
+## Ubuntu 14.04
 ```
 $ sudo apt-get install make unrar autoconf automake libtool gcc g++ gperf \
     flex bison texinfo gawk ncurses-dev libexpat-dev python sed
 ```
 
+## MacOS:
+```bash
+$ brew tap homebrew/dupes
+$ brew install binutils coreutils automake wget gawk libtool gperf gnu-sed --with-default-names grep
+$ export PATH="/usr/local/opt/gnu-sed/libexec/gnubin:$PATH"
+```
+
+In addition to the development tools MacOS needs a case-sensitive filesystem.
+You might need to create a virtual disk and build esp-open-sdk on it:
+```bash
+$ sudo hdiutil create ~/Documents/case-sensitive.dmg -volname "case-sensitive" -size 10g -fs "Case-sensitive HFS+"
+$ sudo hdiutil mount ~/Documents/case-sensitive.dmg
+$ cd /Volumes/case-sensitive
+```
+
 For other Debian/Ubuntu versions, dependencies may be somewhat different.
 E.g. you may need to install libtool-bin, etc.