MCPATH is a Unix environment variable that defines directories for McIDAS-X commands to search when they look for data and help files. Commands requiring these files look in each of the directories listed in MCPATH to find them.
MCPATH has a default value that automatically locates the data files that required linking or redirection in previous versions of McIDAS-X. If users elect to set their own MCPATH value, they only need to know the directories where the files reside, not the exact file names.