To avoid this issue, we should always check the length of COMMAREA by comparing EIBCALEN and data-area-length in LENGTH option of LINK, XCTL or RETURN command. If the receiving data area is longer than the original communication area, the transaction might attempt to read or write data outside the area that has been passed which might cause CICS to abend. The receiving data area can be the same length or shorter than the original communication area but must not be longer. The first program which creates the COMMAREA can define it in working-storage section and the rest of the programs should have it as DFHCOMMAREA in Linkage section. The programs involved in communication can add the COMMAREA either in working-storage section or linkage section based on its hierarchy level. Because the CICS programs must agree on the format and use of the data definitions in the COMMAREA, this area is usually mapped by a single COBOL data. The RETURN command COMMAREA option specifies the data area name in which data is passed to the transaction identified in the TRANSID option.

The LINK and XCTL commands COMMAREA option specifies the data area name in which data is passed to the program being invoked. COMMAREA is an option of the LINK, XCTL, and RETURN commands. The maximum length of the data can be passed through COMMAREA is 64K.īut the recommended length is 24K and it is not preferred to pass more than 24K. This document describes using the COBOL Mapping Editor to extract from a CICS DFHCOMMAREA program where COBOL output parameters are the same as COBOL input parameters, that is, the DFHCOMMAREA on output is not overlaid with a data structure different to the data structure on input. COMMAREA is the name of the data area in which the data or information transferred from one program to another program.

Dfhcommarea in cobol program