Retrieves a comment above key from group_name.
If key is NULL then comment will be read from above
group_name. If both key and group_name are NULL, then
comment will be read from above the first group in the file.
Note that the returned string does not include the '#' comment markers,
but does include any whitespace after them (on each line). It includes
the line breaks between lines, but does not include the final line break.
Retrieves a comment above key from group_name. If key is NULL then comment will be read from above group_name. If both key and group_name are NULL, then comment will be read from above the first group in the file.
Note that the returned string does not include the '#' comment markers, but does include any whitespace after them (on each line). It includes the line breaks between lines, but does not include the final line break.