The IMPORT UNFORMATTED statement does not read the last line within a text file if there is no carriage-return at the end of the file.
The IMPORT UNFORMATTED statement does not read the last line within a text file if there is no line-feed at the end of the file.
If there is no new-line at the end of a line, the IMPORT ignores the line and the previous line is repeated.

Examle ABL code using IMPORT UNFORMATTED

DEFINE VARIABLE text-string AS CHARACTER FORMAT "x(76)".

INPUT FROM "TextFileWithOneLineAndNoCarriageReturn.txt".

DO WHILE TRUE ON ENDKEY UNDO, LEAVE:
  IMPORT UNFORMATTED text-string.
  DISPLAY text-string WITH DOWN FRAME x.
  DOWN WITH FRAME x NO-LABELS.
END.

INPUT CLOSE. 

Example ABL to create text input files:

DEFINE VARIABLE oLEN AS INTEGER     NO-UNDO.

oLEN = (IF OPSYS = "WIN32" THEN 2 ELSE 1).

OUTPUT TO "inptext1.txt".
PUT UNFORMATTED "this input file" SKIP "is short".
OUTPUT CLOSE.

OUTPUT TO "inptext2.txt".
PUT UNFORMATTED "this input file" SKIP 
    "has no terminating EOL" + FILL("x",1962 - oLEN) "Y".
OUTPUT CLOSE.

OUTPUT TO "inptext3.txt".
PUT UNFORMATTED "this input file" SKIP 
    "has no terminating EOL" + FILL("x",1962 - oLEN) "ABCDEFGHIJKLMNOPQRSTUVWXYZ".
OUTPUT CLOSE.

OUTPUT TO "inptext4.txt".
PUT UNFORMATTED "this input file".
OUTPUT CLOSE.

Upgrade to 12.0 or later. Rather than lose the data on the last line, in OpenEdge 12.0 and above return the value from the last line, and handle the EOF as an EOL.

 

The UNFORMATTED option forces IMPORT to read one physical line at a time:

• The input data must not contain embedded control characters within the line, each line must be terminated by a Line Feed character or new line carriage-return and ensure there is a newline to the end of the file.
• A physical line ends with a new line carriage-return or line-feed character. 
• If the text file doesn't end with a line-feed character the IMPORT UNFORMATTED statement will not be able to read the last line of the text file and the second last line is returned twice.

Note: Since OpenEdge 12, the behaviour of the IMPORT UNFORMATTED statement has changed: the value from the last line is returned and the EOF is handled as an EOL.  There was NO reversion switch/parameter provided to roll back this change. 

The default behavior from 12.0 forward is to use the EOF character as a EOL character.

In releases prior to OpenEdge 12, use the COPY-LOB statement to copy the full content of the text file to a LONGCHAR variable.

For example:

DEFINE VARIABLE lc AS LONGCHAR   NO-UNDO.
DEFINE VARIABLE c AS CHARACTER   NO-UNDO.

COPY-LOB FILE "TextFileWithOneLineAndNoCarriageReturn.txt" TO lc.
c = lc. /* assuming lc is less than 32k */

MESSAGE c
    VIEW-AS ALERT-BOX INFO BUTTONS OK. 

The following Article provides an example to add a Line Feed character at the end of the text file programmatically:

1. On Windows, INPUT FROM "CLIPBOARD will also show this behavior, but the clipboard is not a valid source for COPY-LOB.

2. When reading from a dedicated input device such as a Barcode Reader, the devices themselves can usually be configured to send a carriage return / linebreak after the last data.

References to Other Documentation: