Mainframe Adventures

Since I discovered MVS 3.8j Tur(n)key 4-, I've been dedicating insanely amount of hours on it. And here I'm sharing my adventures.

Poor Man's MVS Scheduler (PMMSSCHD)

A scheduler for MVS 3.8j Tur(n)key 4-.

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MVS 3.8j TOOLBOX

Useful (at least to me) JCLs for MVS 3.8j

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COVID-19 Report

In this project I created a series of programs for Linux and MVS 3.8j TK4- to get daily COVID-19 data and generate reports.

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OS/VS COBOL V1R2M4 (Prod# 5740-CB1) for MVS 3.8

This are just some examples I'm putting together meanwhile I re-learn COBOL.

I'm by no means an expert on COBOL or mainframes, so use it with caution. My experience with COBOL was circa 1997-2006 on OS/390 and AS/400.

If you have any snippets you would like to share or you think my code can be improved, please fill free to create a Pull Request.

Many thanks to the folks at https://groups.io/g/H390-MVS that helped me to finish READSEQ.

• TEMPLATE: Template with (almost) all DIVISION and SECTION.
• CONDITIO: Example of use of conditional statements (IF/ELSE, IF NOT, SIGN, CLASS, CONDITION-NAME, AND).
• ARITHMET: Example of arithmetic operations (ADD, SUBTRACT, MULTIPLY, DIVIDE, COMPUTE).
• ACCEPT: Accept (receive) a value from SYSIN.
• TABLES: Examples of tables (arrays).
• EXAMIN: Some usages of EXAMINE (similar to INSPECT in z/OS COBOL).
• CALLSUB1: Example of calling by REFERENCE a COBOL subroutine.
• CALLSUB3: Subroutine to be called (cannot be executed independently).
• STRUSTR: This COBOL does not have STRING/UNSTRING. Here is how to do it instead.
• DAYOWEEK: Calculate which day of the week, using Zeller's congruence algorithm.
• SEQAPPND: Example of use of WRITE and DISP=MOD to append to a Sequential file.
• SEQREAD: Example of use of READ and DISPLAY with a Sequential file.
• SEQREWRT: Example of use REWRITE to change a record on a Sequential file.
• SEQWRITE: Example of use WRITE and DISP=SHR to write (overwritting) records to a Sequential file.
• TRANSFRM: Example of TRANSFORM statement to alter characters.

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IBM Enterprise COBOL for zOS

I had a brief access to an IBM Z mainframe, but now it's gone so do not expect much more to come here.

• TEMPLATE: Template with (almost) all DIVISION and SECTION.
• CONDITIO: Example of use of conditional statements (IF/ELSE, IF NOT, SIGN, CLASS, CONDITION-NAME, EVALUATE, AND/OR).
• ARITHMET: Example of arithmetic operations (ADD, SUBTRACT, MULTIPLY, DIVIDE, COMPUTE).
• ACCEPT: Accept (receive) a value from SYSIN.
• ARRAYS: Example of arrays (TABLE).
• STRINGS: Example of string manipulation.
• WRITESEQ: Example of use WRITE to add records to a Sequential file.
• READSEQ: Example of use of READ and DISPLAY with a Sequential file.
• READSEQ2: Example of use of READ, DISPLAY and STRING with a Sequential file.
• REWRTSEQ: Example of use REWRITE to change a record on a Sequential file.
• CALLSUB1: Example of calling by REFERENCE a COBOL subroutine.
• CALLSUB2: Example of calling by CONTENT a COBOL subroutine.
• CALLSUB3: Subroutine to be called (cannot be executed independently).
• SUBMIJCL: Submit a JCL via Internal Reader (INTRDR).
• $EXECSUB: JCL to execute SUBMIJCL.