#13012: use splitlines(keepends=True/False) instead of splitlines(0/1).
diff --git a/Lib/codecs.py b/Lib/codecs.py
index b150d64..e63a0c6 100644
--- a/Lib/codecs.py
+++ b/Lib/codecs.py
@@ -484,7 +484,7 @@
                 if firstline:
                     newchars, decodedbytes = \
                         self.decode(data[:exc.start], self.errors)
-                    lines = newchars.splitlines(True)
+                    lines = newchars.splitlines(keepends=True)
                     if len(lines)<=1:
                         raise
                 else:
@@ -526,7 +526,7 @@
                 self.charbuffer = self.linebuffer[0]
                 self.linebuffer = None
             if not keepends:
-                line = line.splitlines(False)[0]
+                line = line.splitlines(keepends=False)[0]
             return line
 
         readsize = size or 72
@@ -543,7 +543,7 @@
                     data += self.read(size=1, chars=1)
 
             line += data
-            lines = line.splitlines(True)
+            lines = line.splitlines(keepends=True)
             if lines:
                 if len(lines) > 1:
                     # More than one line result; the first line is a full line
@@ -559,10 +559,10 @@
                         # only one remaining line, put it back into charbuffer
                         self.charbuffer = lines[0] + self.charbuffer
                     if not keepends:
-                        line = line.splitlines(False)[0]
+                        line = line.splitlines(keepends=False)[0]
                     break
                 line0withend = lines[0]
-                line0withoutend = lines[0].splitlines(False)[0]
+                line0withoutend = lines[0].splitlines(keepends=False)[0]
                 if line0withend != line0withoutend: # We really have a line end
                     # Put the rest back together and keep it until the next call
                     self.charbuffer = self._empty_charbuffer.join(lines[1:]) + \
@@ -575,7 +575,7 @@
             # we didn't get anything or this was our only try
             if not data or size is not None:
                 if line and not keepends:
-                    line = line.splitlines(False)[0]
+                    line = line.splitlines(keepends=False)[0]
                 break
             if readsize < 8000:
                 readsize *= 2
@@ -803,7 +803,7 @@
 
         data = self.reader.read()
         data, bytesencoded = self.encode(data, self.errors)
-        return data.splitlines(1)
+        return data.splitlines(keepends=True)
 
     def __next__(self):