ABAP Keyword Documentation → ABAP − Reference → Processing External Data → ABAP File Interface → Statements for the ABAP File Interface → OPEN DATASET
OPEN DATASET - access
Other versions: 7.31 | 7.40 | 7.54
Syntax
... INPUT
| OUTPUT
| APPENDING
| UPDATE ...
Alternatives
2. ... OUTPUT
3. ... APPENDING
4. ... UPDATE
Effect
These mandatory additions are used to open the file for reading, writing, appending, or changing.
Alternative 1
... INPUT
Effect
The addition FOR INPUT opens the file for reading. By default, the file pointer
is set to the start of the file. If the file specified does not exist, sy-subrc is set to 8. Writes cannot be performed on a file opened for reads.
Example
Opens a binary file to read binary data.
DATA(dset) = 'test.dat'.
OPEN DATASET dset FOR INPUT IN BINARY MODE.
Alternative 2
... OUTPUT
Effect
The addition FOR OUTPUT opens the file for writing. If the specified file
already exists, its content is deleted. If the file specified does not exist, it is created. Reads are also permitted.
Example
Opens a binary file to write binary data.
DATA(dset) = 'test.dat'.
OPEN DATASET dset FOR OUTPUT IN BINARY MODE.
Alternative 3
... APPENDING
Effect
The addition FOR APPENDING opens the file for appending. If the file specified
already exists, it is opened and the file pointer is set at the end of the file. If the file specified
does not exist, it is created. Attempted reads to a file opened with FOR APPENDING
with the statement READ DATASET fail, and return the value 4 for sy-subrc.
Example
Opens a binary file to append binary data.
DATA(dset) = 'test.dat'.
OPEN DATASET dset FOR APPENDING IN BINARY MODE.
Alternative 4
... UPDATE
Effect
The addition FOR UPDATE opens the file for changes to the existing content.
By default, the file pointer is set to the start of the file. If the specified file does not exist, no file is opened and sy-subrc is set to 8.
Example
Opens a binary file to update binary data.
DATA(dset) = 'test.dat'.
OPEN DATASET dset FOR UPDATE IN BINARY MODE.