Update ReadMe.md

wolf_scripts/ReadMe.md

@@ -10,6 +10,56 @@ Helpful scripts to create WOLF tree elements (e.g. processors)
   
   ..*`sudo apt-get install realpath`
   
+  * __RealPath__ (Required, MacOSX): The realpath package above is not available for MacOSX. Here is an out-of-the-box alternative (credits to WaffleSouffle: https://stackoverflow.com/questions/3572030/bash-script-absolute-path-with-osx):
+  
+    - Create a small project `realpath` (here in `$HOME/dev/` as an example)
+
+    $ cd $HOME/dev
+    $ mkdir realpath
+    
+    - Create a file `realpath.c` with the contents:
+  
+    ```c
+    // realpath.c
+	#include <stdio.h>
+	#include <stdlib.h>
+
+	int main (int argc, char* argv[])
+	{
+  		if (argc > 1) {
+    			for (int argIter = 1; argIter < argc; ++argIter) {
+      			char *resolved_path_buffer = NULL;
+      			char *result = realpath(argv[argIter], resolved_path_buffer);
+
+      			puts(result);
+
+      			if (result != NULL) {
+        				free(result);
+      			}
+    			}
+  		}
+
+  	return 0;
+	}
+	```
+	
+	- Create a file `Makefile` with the contents (leading whitespace are TABs!!)
+	
+	```
+	#Makefile
+	OBJ = realpath.o
+
+	%.o: %.c
+		$(CC) -c -o $@ $< $(CFLAGS)
+
+	realpath: $(OBJ)
+		gcc -o $@ $^ $(CFLAGS)
+	```
+	
+	- Then compile with make and put in a soft link with:
+	
+    $ ln -s $(pwd)/realpath /usr/local/bin/realpath
+  
 #### SCRIPTS installation  
 
   * Move to the scripts folder