Transitioning from Micro Focus COBOL to Dell Enterprise COBOL

Transcription

1 Transitioning from Micro Focus COBOL to Dell Enterprise COBOL Solution overview November 2013 Dell delivers comprehensive COBOL application development, maintenance and modernization technologies that optimize IT resources, improve business performance and dramatically lower cost. Organizations are converting applications from Micro Focus COBOL platforms, such as Micro Focus Server Express and Net Express, to Dell technology for many reasons including: To gain the advantage of a COBOL development and Java deployment model, without rewriting or retraining To improve return on investment (ROI) and dramatically lower COBOL licensing fees To deploy to multiple platforms using a single set of source code To natively integrate with leading web and application server technologies To support a wide range of data access options and capabilities

2 Table of contents Introduction... 1 Dell Enterprise COBOL...3 Phased transition option...3 Migration process overview...3 Compiler options... 4 Command-line options... 4 Language syntax...5 Runtime configuration variables (properties)...5 Environment variables...5 Accommodating variations...5 Data access... 6 Sequential files... 6 Relative files... 6 Indexed files... 6 Relational databases... 6 External file systems... 6 File status codes... 6 User interfaces...7 Interoperability...7 Library routines...7 Phased transitions... 8 For more information

3 Dell provides compiler and runtime compatibility settings to keep the overall level of effort required for conversion to a minimum. Introduction Dell Enterprise COBOL Dell Enterprise COBOL (formerly vcobol Enterprise) provides a powerful environment for you to develop and deploy your businesscritical COBOL applications on open systems. Legacy COBOL dialect support enables you to migrate existing interactive and batch environments, as well as stand-alone application deployments, with little or no code change. Dell Enterprise COBOL includes: Powerful COBOL compiler: Produce optimized object code that you can deploy on a variety of platforms, such as Linux and Microsoft Windows, to take full advantage of 32- or 64-bit deployments Streamlined, portable runtime environment: Improve performance in many common enterprise scenarios with a runtime environment designed to minimize overhead and provide optimized access to data Flexible, visual studio-based integrated development environment: Provide your COBOL programmers with a single, flexible environment for all development tasks (design, coding, testing and debugging) in a widely accepted and extensible framework Wide range of data access capabilities: Simplify transitions to the Dell Enterprise COBOL platform with support for all common COBOL file organizations, record types and relational databases Phased transition option With Dell, organizations have the choice of either migrating an entire application codebase at once or taking a phased approach, which sets the pace of a conversion according to resource availability and desired timeframe. During a phased migration, an organization s development team can continue to maintain an application with the Micro Focus COBOL compiler, while simultaneously working on the same set of source code to compile and execute with the Dell Enterprise COBOL compiler. Dell provides compiler and runtime compatibility settings to keep the overall level of effort required for conversion to a minimum. Migration process overview The key steps involved in a conversion to the Dell Enterprise COBOL platform are: 1. Set up Dell Enterprise COBOL 2. Recompile the application; review compiler output, and make minor syntax modifications where necessary 3. Migrate data, if necessary, using Dell-supplied conversion utilities 4. Set up the target platform runtime environment including runtime properties and data connections 5. Integrate with external software libraries and routines, such as those written in the C programming language In order to rapidly convert Micro Focus COBOL programs and data files to Dell Enterprise COBOL, your organization needs a better understanding of the elements that make a successful conversion including: Compiler options, data access, user interfaces, interoperability requirements and the phased transition approach. 3

4 Compiler options Dell Enterprise COBOL includes a 100 percent portable COBOL compiler, which supports the latest ANSI standards as well as common legacy dialects. Developers do not need to be familiar with the Java programming language in order to work with the Dell Enterprise COBOL compiler, as all development and debugging is done in the COBOL language. The Dell Enterprise COBOL compiler can operate as a command-line utility, just like Micro Focus COBOL. Existing Micro Focus build scripts can be used in a Dell Enterprise COBOL environment by changing relevant compiler executable names and command-line options. Dell Enterprise COBOL offers a high degree of compatibility with Micro Focus COBOL syntax; and, for those parts of an application that rely on Micro Focusspecific semantics, compatibility options for compilation and runtime behavior are provided. Command-line options Dell Enterprise COBOL and Micro Focus COBOL use significantly different conventions for specifying compiler options at the command line and in application source code. Dell Enterprise COBOL uses standard command-line style options, whereas Micro Focus COBOL uses its own compiler directive style. With Dell Enterprise COBOL, commandline options start with a hyphen, followed by an abbreviation. In some cases, the abbreviation is followed by an equal sign and then a value. These command-line style options can be specified in a file using the vcobol. compiler.options property. For example, to provide compatibility with the mainframe behavior of the PERFORM statement such as on OS/VS COBOL: Micro Focus COBOL requires the compiler directive PERFORM-TYPE OSVS Dell Enterprise COBOL requires the compiler command-line option -pt2 For another example, to specify a list of directories for the compiler to search for copy files: Micro Focus COBOL requires the compiler directive COPYPATH list-of-directories Dell Enterprise COBOL requires the compiler command-line option -sp=list-of-directories Tip: To specify the directories with an environment variable named COBCPY, use -sp=$cobcpy on Linux and -sp=%cobcpy% on Windows. Dell Enterprise COBOL uses standard command-line style options, whereas Micro Focus COBOL uses its own compiler directive style. 4

5 The Dell support team has considerable experience migrating from the Micro Focus platform. Language syntax Small code changes may need to be made to items such as inline comments. For example: 01 WS-VAR PIC X. // Micro Focus inline comment 01 WS-VAR PIC X. Dell Enterprise COBOL inline comment Runtime configuration variables (properties) At runtime, there are a number of Dell Enterprise COBOL properties that affect application behavior. These properties can be adjusted to obtain the same behavior as Micro Focus COBOL. For example, a default behavior of Micro Focus COBOL is to strip trailing spaces from line-sequential file records during WRITE operations. The same behavior can be obtained in a Dell Enterprise COBOL environment by setting the runtime property to vcobol.file.strip_ trailing_spaces=true. Accommodating variations The Dell support team has considerable experience migrating from the Micro Focus platform. In areas where Dell Enterprise COBOL does not support specific Micro Focus COBOL syntax, the desired behavior can be obtained using recommended changes to the syntax. In addition, the effect of a particular Micro Focus compiler directive can be obtained using a recommended Dell Enterprise COBOL compiler option or runtime setting. The following list maps commonly used Micro Focus directives to the appropriate Dell Enterprise COBOL alternative: Micro Focus COBOL directive Dell Enterprise COBOL alternative ANIM APOST -d -apost Another example is accommodating the Micro Focus RTS Switch N, which is default behavior in Micro Focus COBOL for including computational data in line-sequential files. This behavior is obtained with Dell Enterprise COBOL by setting the property to vcobol.file. linesequential=com.dell.vcobol.runtime. base.io.dynamiclseqmf_n. Environment variables With both Micro Focus COBOL and Dell Enterprise COBOL, the same programming syntax is used to get and set environment variables. However, there are differences in behavior if non- COBOL software is involved. Please contact a Dell Services representative for more information. ASSIGN(EXTERNAL) COPYEXT(cpy) DEFAULTBYTE(00) IBMCOMP PERFORM-TYPE(OSVS) REMOVE(NULL) NOTRUNC -cax -ce=cpy -dv=0 -dcmi -pt2 -rw=null -dz 5

6 Data access The innovative and modular design approach supports a wide range of data access options. All common COBOL file organizations and record types are supported by Dell Enterprise COBOL including indexed, relative, binary sequential and line sequential, with fixed and variable length records. Embedded SQL (ESQL) is supported either through database-specific precompilers, such as Oracle Pro*COBOL and DB2 PRECOMPILE, or through Java Database Connectivity (JDBC). In the latter case, no ESQL precompiler is required. To support JDBC, the Dell Enterprise COBOL compiler has a built-in ESQL compiler that translates EXEC SQL statements into calls to JDBC. No separate precompilation step is required. Most data files will need to be converted to an equivalent Dell format before they can be used. A data migration utility is included with the Dell Enterprise COBOL runtime environment. Sequential files Micro Focus COBOL and Dell Enterprise COBOL employ the same techniques to determine record lengths, so neither fixed-length nor variable-length sequential files require conversion. Relative files Relative files can be converted with a utility provided by Dell support. Indexed files Indexed files can be easily converted to Dell JISAM, a 100 percent Java-based indexed sequential access method (ISAM) file system. Dell JISAM includes a file-management utility, JUTIL, that has an option for automatically migrating Micro Focus indexed data files into the Dell JISAM file format. Relational databases No data migration is required for relational databases when moving to a Dell Enterprise COBOL platform current databases can continue to be accessed through existing interfaces without COBOL code changes. Dell Enterprise COBOL supports access to any database that offers a JDBC driver or a COBOL/ESQL precompiler. Databases can be accessed through standard COBOL file I/O (input/output) statements or by including embedded SQL in the COBOL source code. External file systems Dell Enterprise COBOL can be configured to use external file systems that contain indexed, relative or sequential files via an EXTFH (external file handler) interface. Developers can set the property to vcobol.extfh. libname to specify the name of the EXTFH library. I/O statements remain the same in the COBOL source, whether using native or EXTFH file system libraries. File status codes To further simplify the transition to Dell Enterprise COBOL, developers can configure the runtime to generate the same file status codes as those used by Micro Focus COBOL. This is accomplished by setting the property to vcobol.file.status= MF. 6

7 User interfaces Because Dell Enterprise COBOL was designed to support back-end transaction processing, the user interface commonly associated with a Dell Enterprise COBOL environment is typically handled by external software such as a transaction processing monitor (e.g., Dell Transaction Processing Environment software, as part of our mainframe re-hosting solution), web or Java server technology, or a third-party screen package. The user interface may also be written in Microsoft Visual Basic, C# (or other Microsoft.NET language). Or the user interface could be a C routine interfacing with a terminal. In all of these cases, the user interface is external to the COBOL applications themselves and would be supported as is, without any migration requirements on the Dell Enterprise COBOL platform. Interoperability Programs compiled with Dell Enterprise COBOL can call external language routines without the need for code changes. Runtime framework properties are used to point to the external libraries. Library routines Dell Enterprise COBOL implements many library routines that provide equivalent functionality to the Micro Focus call-by-name routines (CBL_*). Where necessary, the Dell support team can write or assist in writing required subroutines, C routines or Java programs using the equivalent Dell Enterprise COBOL syntax. The table in the right column identifies Micro Focus library routines that are supported by Dell Enterprise COBOL: Micro Focus library routines that are supported by Dell Enterprise COBOL CBL_ALLOC_MEM CBL_AND CBL_CHANGE_DIR CBL_CHECK_FILE_EXIST CBL_CLOSE_FILE CBL_COPY_FILE CBL_CREATE_DIR CBL_CREATE_FILE CBL_DELETE_DIR CBL_DELETE_FILE CBL_DIR_SCAN_END CBL_DIR_SCAN_READ CBL_DIR_SCAN_START CBL_ERROR_PROC CBL_EXIT_PROC CBL_FLUSH_FILE CBL_FREE_MEM CBL_FREE_RECORD_LOCK CBL_GET_RECORD_LOCK CBL_NOT CBL_OPEN_FILE CBL_OR CBL_READ_FILE CBL_RENAME_FILE CBL_TEST_RECORD_LOCK CBL_WRITE_FILE CBL_XOR 7

8 Phased transitions With Dell Enterprise COBOL compiler and runtime compatibility settings, the overall effort required to move from Micro Focus COBOL can be kept to a minimum. Some organizations still elect to undergo a phased migration to further minimize business disruption when migrating to Dell Enterprise COBOL. During a phased transition, developers continue to maintain an application with the Micro Focus COBOL compiler and to support current customers under the Micro Focus platform, while simultaneously working on the same set of source code in Dell Enterprise COBOL. If specific features are desired for use with the Dell Enterprise COBOL platform, conditional compilation options are employed and a check is performed at runtime to determine which subprogram to call. Some of the Dell Enterprise COBOL features that make phased transition possible include: The compiler operates as a commandline utility, like Micro Focus COBOL. So, current build scripts can be used by changing only the compiler executable name and command-line options. Dell Enterprise COBOL compatibility options for proprietary Micro Focus brand features. Dell Enterprise COBOL compiler support for conditional compilation with Micro Focus style syntax, allowing the preservation of current COBOL syntax and behavior. Runtime environment support for checking at runtime to determine whether the execution environment is set for Dell Enterprise COBOL or Micro Focus COBOL. This ability to do dual coding within the same program allows you have a single set of source code for your application, even as you convert. Dell Enterprise COBOL is stricter in some areas about ANSI COBOL standards than other compilers and might, therefore, catch new programming errors. Once an application s standards compliance has been improved, the code will compile cleanly with Micro Focus COBOL as well as with Dell Enterprise COBOL. Conclusion Our innovative COBOL technology is highly compatible with today s common COBOL dialects, enabling quick and efficient migration from Micro Focus COBOL. Whether your organization is focused on evolving existing applications through service-oriented architecture (SOA), migrating from mainframes to open systems, improving quality and distribution processes or simply improving the bottom line, Dell Enterprise COBOL can increase business productivity and operational effectiveness. When considering a move to Dell Enterprise COBOL, our support team can help assess the level of effort required. If desired, Dell also offers services to build a limited representative prototype of an application running in a Dell Enterprise COBOL environment. This exercise includes a thorough analysis process that helps determine how straightforward the transition to Dell Enterprise COBOL will be for an organization. For more information on migrating to Dell Enterprise COBOL, please visit us online at Dell.com/cobol or contact your Dell representative. Scan or click this code to learn how Dell Services can help your organization. This product or document is protected by copyright and distributed under licenses restricting its use, copying, distribution and recompilation. No part of this product or document may be reproduced in any form by any means without prior written authorization of Dell and its licensors, if any. Windows and Visual Studio are registered trademarks of Microsoft Corporation. Oracle and Java are registered trademarks of Oracle and/or its affiliates. Other names may be trademarks of their respective owners Dell Inc. One Dell Way, Round Rock, Texas 78682, USA. All rights reserved. November 2013 D351 - Micro Focus COBOL to Dell Enterprise COBOL.indd Rev. 1.2