As a rule of thumb, DOS, Windows, OS/2 and many internet protocols use CR+LF, classic Macs use CR only, Unix and its derivates including modern Macs and the remaining internet protocols use LF only. They all use ASCII. Things become worse on EBCDIC systems, typically made by IBM. See Newlines in perlport.

Look at a hex dump of the export, it will surely help more than guessing.

od -t x1c demo.csv
0000000 22 48 65 61 64 69 6e 67 20 31 22 2c 22 48 65 61
          "   H   e   a   d   i   n   g       1   "   ,   "   H   e   
+a
0000020 64 69 6e 67 20 32 22 2c 22 48 65 61 64 69 6e 67
          d   i   n   g       2   "   ,   "   H   e   a   d   i   n   
+g
0000040 20 33 22 2c 22 48 65 61 64 69 6e 67 20 34 22 0d
              3   "   ,   "   H   e   a   d   i   n   g       4   "  \
+r
0000060 0a 22 44 61 74 61 20 31 22 2c 22 44 61 74 61 20
         \n   "   D   a   t   a       1   "   ,   "   D   a   t   a
0000100 32 22 2c 22 44 61 74 61 20 33 22 2c 22 44 61 74
          2   "   ,   "   D   a   t   a       3   "   ,   "   D   a   
+t
0000120 61 20 34 22 0d 0a 22 4d 6f 72 65 20 31 22 2c 22
          a       4   "  \r  \n   "   M   o   r   e       1   "   ,   
+"
0000140 4d 6f 72 65 20 32 22 2c 22 4d 6f 72 65 20 33 22
          M   o   r   e       2   "   ,   "   M   o   r   e       3   
+"
0000160 2c 22 4d 6f 72 65 20 34 22 0d 0a
          ,   "   M   o   r   e       4   "  \r  \n
0000173
[download]

This particular CSV file ends each line with two bytes 0x0D and 0x0A, which is equal to \015\012 on ALL platforms. If you read the file on a Unix-based system or in binary mode on a DOS-based system, you can also use \r\n. If you read the file in text mode on a DOS-based system, use only \n. You can get the same behaviour on Unix-based system using the :crlf PerlIO layer.

Alexander