The following code example fails to allocate memory due to limited Operating System resources and generates an ambiguous error without supporting messages why the COPY-LOB from a MEMPTR to a LONGCHAR failed:

Large object assign or copy failed. (11395)

DEFINE VARIABLE mpVar AS MEMPTR      NO-UNDO.
DEFINE VARIABLE mpVar2 AS MEMPTR      NO-UNDO.
DEFINE VARIABLE lcVar AS LONGCHAR      NO-UNDO.
DEFINE VARIABLE iSize AS INTEGER     NO-UNDO.

ASSIGN
    FILE-INFO:FILE-NAME = "Bug.txt" /* "Bug.txt" file size = 501 MB (526,112,370 bytes) */
    iSize = FILE-INFO:FILE-SIZE
    SET-SIZE(mpVar) = iSize
    SET-SIZE(mpVar2) = iSize.

/* Read file into the MEMPTR variable */
INPUT FROM "Bug.txt" BINARY NO-MAP NO-CONVERT.
    IMPORT mpVar.
INPUT CLOSE.

/* This statement generates the error: Large object assign or copy failed. (11395) */
COPY-LOB FROM mpVar STARTING AT 1 FOR iSize TO lcVar.

SET-SIZE(mpVar) = 0.

MESSAGE GET-SIZE(mpVar) GET-SIZE(mpVar)  LENGTH(lcVar)
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If the above code is modified to copy from the MEMPTR variable to another MEMPTR variable, then the more helpful error (11325) is generated:

1. Read the file in smaller chunks of 200MB each into a MEMPTR variable mpVariable.
2. Copy each chunk into a temporary LONGCHAR variable lcTempoary.
3. Append the temporary LONGCHAR variable lcTempoary to the target LONGCHAR variable lcVariable.

DEFINE VARIABLE mpVariable AS MEMPTR      NO-UNDO.
DEFINE VARIABLE lcVariable AS LONGCHAR    NO-UNDO.
DEFINE VARIABLE lcTempoary AS LONGCHAR    NO-UNDO.

DEFINE VARIABLE chVariable AS CHARACTER  NO-UNDO.

DEFINE VARIABLE iFileSize  AS INTEGER    NO-UNDO.
DEFINE VARIABLE iRemaining AS INTEGER    NO-UNDO.
DEFINE VARIABLE iChunkSize AS INTEGER    NO-UNDO.
DEFINE VARIABLE iMptrSize  AS INTEGER    NO-UNDO.
DEFINE VARIABLE iLoopCount AS INTEGER    NO-UNDO.


ASSIGN
    FILE-INFO:FILE-NAME = "Bug.txt"
    iFileSize          = FILE-INFO:FILE-SIZE /* Actual file size 501 MB (526,112,370 bytes) */
    iChunkSize          = MIN(200 * 1024 * 1024, iFileSize)
  
/*  
    NOTE: The size of the chunk may need to be adjusted depending on the RAM available.  
    For example, using 100MB chunk size the statement
    lcVariable = lcVariable + lcTempoary.
    may still fail but this time with a more helpful error: 
    Could not allocate memory to perform concatenate operation (15633)
*/
   
    iMptrSize        = iChunkSize
    SET-SIZE(mpVariable)    = iMptrSize
    iLoopCount = 0.

iRemaining = iFileSize.
REPEAT WHILE iRemaining > iChunkSize:
    COPY-LOB FROM FILE "Bug.txt" STARTING AT iLoopCount * iMptrSize + 1 FOR  iMptrSize TO mpVariable NO-ERROR.
    COPY-LOB FROM mpVariable STARTING AT 1 FOR iMptrSize TO lcTempoary.
    ASSIGN
        iLoopCount = iLoopCount + 1
        iRemaining = iRemaining - iMptrSize
        lcVariable = lcVariable + lcTempoary
        iMptrSize = MIN(iChunkSize, iRemaining)
        SET-SIZE(mpVariable) = 0.
    SET-SIZE(mpVariable) = iMptrSize.
END.

ASSIGN
    iLoopCount = iLoopCount - 1
    iMptrSize = iRemaining
    SET-SIZE(mpVariable) = iMptrSize.

COPY-LOB FROM FILE "Bug.txt" STARTING AT iLoopCount * iMptrSize + 1 FOR  iMptrSize TO mpVariable NO-ERROR.
COPY-LOB FROM mpVariable STARTING AT 1 FOR GET-SIZE(mpVariable) TO lcTempoary.

ASSIGN
    SET-SIZE(mpVariable) = 0
    lcVariable = lcVariable + lcTempoary
    chVariable = SUBSTRING (lcVariable, 1, 1000).

MESSAGE LENGTH(lcVariable) "~n"  chVariable
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