In edit->preferences->diff, I have changed the default diff application to my own one.
For the arguments, I have:
%1 %2 "C:/Program Files/path_to_file"
The arguments i get inside my custom tool are:
file represented by %1
file represented by %2
The file names are passed perfectly fine.
Why is it cutting of the path? It's surrounded by quotation marks so surely it should be passed as a single argument?
When running the custom diff tool from visual studio and specifying the above mentioned arguments manually it works fine, so it seems that perforce is cutting the argument at the white space.