What is file control in COBOL?
The FILE-CONTROL paragraph associates each file in the COBOL program with an external data set, and specifies file organization, access mode, and other information. Indexed file entries. Relative file entries. Line-sequential file entries.
How do you read a file in COBOL sample program?
COBOL File Operations
- We should open a file before we perform any operation in it.
- All the files must open in PROCEDURE DIVISION before any other operations are performed in it.
- OPEN INPUT FILE-NAME.
- All the input files must be READ in PROCEDURE DIVISION before the records in the file we use further.
Can we rewrite sequential file in COBOL?
The file must be opened in I-O mode for REWRITE statement. The REWRITE statement is not supported for line-sequential files.
How do I open VSAM files in COBOL?
Because VSAM does not support random or dynamic processing, COBOL has to perform some extra processing to enable you to use ACCESS IS RANDOM or ACCESS IS DYNAMIC with OPEN OUTPUT or OPEN I-O ….Opening an empty file
- Open the file.
- Use sequential processing ( ACCESS IS SEQUENTIAL ).
- Use WRITE to add a record to the file.
How do you read a flat file in COBOL?
PROCEDURE DIVISION. OPEN INPUT FILEX. PERFORM READ-PARA THRU END-PARA UNTIL END-OF-FILE = ‘Y’. CLOSE FILEX.
Can I declare occurs in 01 level?
Why occurs clause cannot be declared at 01 level? according to the manual, a table is defined within a group item with an occurs clause. if the occurs clause were to be declared at the 01 level, there would be no group item, thus no beginning of table resolution.
What is the purpose of 77 level number?
Level 77 is a special level number in COBOL which is used to declare independent data items; they are not subdivisions of other data items and are not subdivided themselves.