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Line Sequential Files

The primary use of line sequential files (which are also known as "text files" or "ASCII files") is for display-only data. Most PC editors, for example Notepad, produce line sequential files.

In a line sequential file, each record in the file is separated from the next by a record delimiter. The record delimiter, which comprises the carriage return (x"0D") and the line feed (x"0A") characters (Windows) or is the line feed (x"0A") character (UNIX), is inserted after the last non-space character in each record. A WRITE statement removes trailing spaces from the data record and appends the record delimiter. A READ statement removes the record delimiter and, if necessary, pads the data record (with trailing spaces) to the record size defined by the program reading the data.

If the record size in a line sequential file is greater than the record length, the data fills the record length and on the next READ it returns more data from that record. i.e. it uses the record length and the record delimiter.

To define a file as line sequential, specify ORGANIZATION IS LINE SEQUENTIAL in the SELECT clause for the file in your COBOL program, for example:

 select lineseq assign to "lineseq.dat"
     organization is line sequential.
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