After reading the answers to this very interesting question and doing some experimenting with SD card for Android (exfat) and a car entertainment system (vfat), I came up whis this little bash script.
# copy music to FAT media
find music/ Music/ -type f | while read f ; do
d=$DST/$( echo $f | sed 's/[^-A-Za-z0-9/._ ()]/_/g' )
mkdir -p "$(dirname "$d")"
cp -n "$f" "$d"
It take the destination (mount point) as it argument and use
find to locate all files in my music repository.
For each file path, it computes a destination path and file name by prepending the destination and replacing any offending character with an underscore
_. I use a white list of characters (letters, digits,
_) to remove any unwanted punctuation.
Depending on the locale, this will leave accented letters in the path and file name, which is OK for modern FAT file systems, as it seems.
For each destination file path and name, the directories are created as needed using
mkdir -p, then the file is copied, unless it already existed.
Note the quote
" chars in various places, they are required to keep paths and names with spaces in them from breaking apart.