Summary of changes

This section lists the major changes that have been made to COBOL for AIX in Version 4. The changes that are described in this information have an associated cross-reference for your convenience. The changes with respect to COBOL for AIX Version 3 (both technical changes and editorial changes to terminology) are marked by a vertical bar (|) in the left margin in the PDF version.

Version 4.1 (September 2010)

  • A new compiler option, ARCH, lets you selectively target code generation of your programs to either exploit POWER7® systems architecture or to be balanced among all supported POWER® systems (ARCH).
  • A new file system, DB2, provides enhanced interoperation with CICS TXSeries, enabling batch COBOL programs to access CICS ESDS, KSDS, and RRDS files that are stored in a DB2 database. An advantage of the DB2 file system is the DB2 database management system (DBMS), which provides backup, compression, encryption, and utility functions, and a familiar maintenance and administration protocol (DB2 file system).
  • The performance of persistent CICS transactions is improved by means of module caching (Tuning the performance of dynamic calls under CICS).
  • Source text can optionally vary in length from 0 to 252 bytes per line (extended source format) or end at column 72 (fixed source format) as in earlier versions of COBOL for AIX. The new extended source format is supported by:
    • A compiler option, SRCFORMAT, which lets you indicate whether source lines have the new extended format or the fixed format that is compatible with earlier versions (SRCFORMAT)
    • A source conversion utility, scu, which helps you normalize non-IBM COBOL source and free-format COBOL source so that it can be compiled (Source conversion utility (scu) (COBOL for AIX Language Reference))
  • Support for generation data groups (GDGs) has been added in all of the COBOL for AIX file systems. GDG catalog and generation management support is provided by a new utility program, gdgmgr (Generation data groups).
  • You can concatenate multiple input files, including individual generation files or entire GDGs, by separating the file identifiers with a colon (:). Concatenation is supported in all of the COBOL for AIX file systems (Concatenating files).
  • A facility for customizing compiler diagnostic messages and FIPS messages by changing their severity or suppressing them is made possible by a new suboption, MSGEXIT, of the EXIT compiler option (EXIT compiler option).
  • A new floating comment indicator (the character string '*>') can be coded in either fixed or extended source format to indicate that the ensuing text on a line is an inline comment.
  • The underscore character (_) is supported in user-defined words such as data-names and program-names. Underscores are also supported in the literal form of program-names.

    For further details, see the COBOL for AIX Language Reference.

  • COBOL source files that have a suffix of either .cbl or .cob are passed to the compiler (Compiling from the command line).
  • The FILESYS runtime option has been extended to enable specification of the SdU (SMARTdata Utilities), SFS (Encina Structured File Server), and DB2 file systems as runtime defaults (FILESYS).

The following terminology change was also made in this release: VSAM as a generic reference to either the SdU (SMARTdata Utilities) or Encina SFS (Structured File Server) file system has been replaced with the more precise terms SdU or SFS where appropriate.