In addition to Hercules for emulation of MVS 3.8 on a PC, there is also the z390 portable mianframe assembler and emulator open source Java J2SE tool. You can download z390 from www.z390.org for installation on Windows XP or Vista using InstallShield. There is also a file image download for Linux which has been tested on Ubuntu Linux.
Once z390 is installed, you can double click on the GUI desktop icon, then enter the command ASMLG demo\DEMO to assemble, link, and execute the HLASM compatible source for a "HELLO WORLD" demo that issues WTO 'HELLO WORLD' message via SVC 35. In addition to GUI interface, z390 can also be run from Windows command line. z390 includes common OS macros such as WTO, TIME, GETMAIN, FREEMAIN, OPEN, CLOSE, GET, PUT, READ, WRITE, CHECK plus structured programming macros including IF, ELSE, ENDIF, DO, ENDO, PERFORM, PEXIT, etc. z390 support all the problem state instructions in the latest POP including DFP, HFP, and BFH floating point instructions. z390 supports AMODE/RMODE 24 and 31 for up to 2 GB memory access. z390 maps QSAM, BSAM, and BDAM I/O onto the host OS file system using J2SE runtime NIO so z390 programs can access any files on the host and share them with other non z390 applications. z390 downloads include all Java source plus lots of demos and regression tests which make it a useful learning tool. For example, there is source for SUPERZAP.MLC structured assembler utility to dump, search, and/or patch any file on the host operating system. z390 supports TCP/IP network communications and SOA type applications using TCPIO SVC for client and server sockets messaging. z390 now has a new CICS compatible transaction manager contributed by Melvyn Maltz supporting multiple TN3270 local and remote clients. Currently z390 support for VSAM is under development to support ESDS, RRDS, and KSDS files with fixed or variable length records up to 2 GB with any number of alternate indexes and file sizes up to 2**63. Don Higgins [EMAIL PROTECTED] ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html