1. Application Runtime for IMS Reference Guide
  2. Oracle Tuxedo Application Runtime for IMS Reference Guide
  3. Configuration Files
  4. Segments Definition - segments.desc

1.10.6 Segments Definition - segments.desc

segments.desc defines the segments within a database. One database (except the GSAM database), has one segments.desc, which is under $ART_IMS_CONFIG/db/$dbname.

The fields in segments.desc are mapped from SEGM statement of DBD.

Table 1-30 segments.desc

[segm]Field Type Value Description Source in SEGM
NAME X(1..8) Mandatory Segment Name NAME
BYTES Integer Mandatory Maximum Length of the segment, 4~32760 BYTES
SEGPGM_A2E X(1..128 ) Optional COBOL Program name used to convert segment data from open system to Mainframe N/A
SEGPGM_E2A X(1..128 ) Optional COBOL Program name used to convert segment data from Mainframe to open system N/A
SSAPGM_A2E X(1..128 ) Optional COBOL Program name used to convert qualified SSA for the segment from open system to Mainframe N/A
KFAPGM_E2A X(1..128 ) Optional COBOL Program name used to convert Key Feedback area for the segment from Mainframe to open system N/A

Note:

For variable length segment, the BYTES definition is mapped from SEGM statement (e.g., BYTES= (max bytes,min bytes)), max bytes must be greater or equal to min bytes. A variable length segment must starts with a 2-byte field, which defines the length of the segment including the 2-byte length field.

For SEGPGM_A2E, SEGPGM_E2A and SSAPGM_A2E, KFAPGM_E2A:

  1. If any of the upper four parameters is not defined in segments.desc, $segname.desc must exist and $segname.desc will be used to do data converting as described later.
  2. SEGPGM_A2E and SEGPGM_E2A.

    SEGPGM_A2E and SEGPGM_E2A must be both defined or both not defined together. When SEGPGM_A2E and SEGPGM_E2A are defined, the ODBA Plugin uses SEGPGM_A2E/ SEGPGM_E2A to do segment data converting, not use the $segname.desc to perform segment data converting even if there is $segname.desc.

    When SEGPGM_A2E and SEGPGM_E2A are not defined, the ODBA plug-in uses the FIELDS definition in $segname.desc to perform segment data converting.
  3. SSAPGM_A2E

    When SSAPGM_A2E is defined, the ODBA plug-in uses the defined COBOL program to do qualified SSA converting for this segment.

    When SSAPGM_A2E is not defined, the ODBA Program uses the KEY Field type definition in $segname.desc to convert the KEY value in the SSA for this segment.
  4. KFAPGM_E2A

    When KFAPGM_E2A is defined, the ODBA plug-in uses the defined COBOL program to do data converting for Key Feedback area for this segment.

    If KFAPGM_E2A is not defined, ODBA program uses the FBAFIELD definition in $segname.desc to do data converting for Key feedback area for this segment.

    For how to generate and compile the upper COBOL programs, please refer to buffer converting in Oracle Tuxedo Application Rehosting Workbench User Guide and Oracle Tuxedo Application Rehosting Workbench Reference Guide.

    Put the compiled converting program under COBPATH (for Micro Focus COBOL) or COB_LIBRARY_PATH (for CIT) before booting Tuxedo ART for IMS servers.

Parent topic: Configuration Files