Reads a record from the sequential file specified in
dsn (a field or a literal) and stores it in the field f
(usually a field string).
Binary mode (addition IN BINARY MODE in the
OPEN DATASET statement:
Read from file in length of field f .
Text mode (addition IN TEXT MODE in the
OPEN statement):
Read a line.
If the specified file is not open, READ DATASET attempts to
open the file dsn ( IN BINARY MODE FOR INPUT or with the
specifications of the last OPEN command for this file). Any
errors result in the termination of the program.
To read all the records in a file, you are recommended to place
READ DATASET in a DO loop that you
leave with EXIT .
The return code value is set as follows:
SY-SUBRC = 0
Record read from file.
SY_SUBRC = 4
End of file reached.
Example
Define the field string REC :
DATA: BEGIN OF REC,
TEXT(30),
NUMBER TYPE I,
END OF REC.
Read the file "/usr/test":
DO.
READ DATASET '/usr/test' INTO REC.
IF SY-SUBRC <> 0.
EXIT.
ENDIF.
WRITE: / REC-TEXT, REC-NUMBER.
ENDDO.
Notes
You can use TRANSFER
to output records to a sequential dataset.
The format of file names depends largely on the operating system. You
can access portable programs by using the function module
FILE_GET_NAME which returns the physical name for a given
logical file name.
Addition
... LENGTH len
Effect
Stores the length of the record read from the file in
the field len .
