VGA Planets originally ran under MS-DOS, which does not distinguish between upper-case and lower-case letters in file names. When PHost is run on Unix or another platform that distinguishes case, one has to decide for one form of file names.
PHost strongly prefers file names in all-lowercase. It contains some provisions to handle all-uppercase names, but this is much underdeveloped and less tested. In particular, PHost does not prevent creating a file with a lower-case name when the upper-case name already exists. Mixed-case names such as HullSpec.Dat are not supported at all.
Hint: Even under Unix-like operating systems such as Linux, partitions formatted with the FAT file-system often behave case-insensitive like under DOS or Windows. You can thus easily avoid all file-name case problems by storing your game directories on a FAT partition.
For compatibility across platforms, PHost uses only 8.3 file names for files it reads or creates by itself. At places where you specify the a directory or file name (for example, when passing PHost a game directory name, or in an Addon statement), you can use longer file names if your environment supports them. However, PHost does not contain any provision for quoting file names for the shell when invoking add-ons (e.g. when you're using a %d placeholder in a PControl command), so you should avoid shell meta-characters and spaces in file names.
