I have never used [man]chunk_split[/man]
but as what I see from manual,
the answer to both your questions is YES.
I would read all submitted comments with code: [man]chunk_split[/man]
chunk_split() splits the string into pieces of N chars length
and inserts custom END between the pieces (maybe after each piece)
string chunk_split ( string $body [, int $chunklen = 76 [, string $end = "\r\n" ]] )