No, Unix does indeed use only \x0A as the line terminator.

$ cat > test
this is a test
this is a test
this is a test
12345678901234
$ od -t x1 test
000000  74  68  69  73  20  69  73  20  61  20  74  65  73  74  0a  74
000020  68  69  73  20  69  73  20  61  20  74  65  73  74  0a  74  68
000040  69  73  20  69  73  20  61  20  74  65  73  74  0a  31  32  33
000060  34  35  36  37  38  39  30  31  32  33  34  0a
000074
$ \ls -l test
-rw-------  1 ikegami  users  60 May 19 09:40 test
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Not only do you see only "0a" without any "0d" in the binary dump, The file size indicates FreeBSD uses only one (60/4 - 14 = 1) character for the newline. From experience, the same applies to Linux, SunOS/Solaris and AIX. The Macs do something different, but I'm not sure what.

Here is the Mac (OS X) output:

brucelowther:~ brucelowther$ cat > ~/tmp/test.txt
this is a test
this is a test
this is a test
12345678901234
brucelowther:~ brucelowther$ hexdump -C  ~/tmp/test.txt
00000000  74 68 69 73 20 69 73 20  61 20 74 65 73 74 0a 74  |this is a
+ test.t|
00000010  68 69 73 20 69 73 20 61  20 74 65 73 74 0a 74 68  |his is a 
+test.th|
00000020  69 73 20 69 73 20 61 20  74 65 73 74 0a 31 32 33  |is is a t
+est.123|
00000030  34 35 36 37 38 39 30 31  32 33 34 0a              |456789012
+34.|
0000003c
[download]

Unemployed!