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In most operating systems, lines in files are terminated by newlines.
+Just what is used as a newline may vary from OS to OS. Unix tradition
+ally uses \012, one type of DOSish I/O uses \015\012, and Mac OS uses
+ \015.
Perl uses \n to represent the "logical" newline, where what is logical
+ may depend on the platform in use. In MacPerl, \n always means \015.
+ In DOSish perls, \n usually means \012, but when accessing a file in
+ "text" mode, STDIO translates it to (or from) \015\012, depending on
+ whether you're reading or writing. Unix does the same thing on ttys
+in canonical mode. \015\012 is commonly referred to as CRLF.