Create a directory from RPG

["Beppe Costagliola" <beppecosta@xxxxxxxx>]

I have to create some directories (with creation of the parent directory if it 
does not exist).

Within CL it works fine using:
QSH CMD('mkdir -p /one/two/three/four')

I've tried QzshSystem from Rpg but I always get error 7. I've checked old 
postings but I did not understand the right way to code.

Thanks for any help.
Giuseppe.