>>> Eric Chavalier wrote: Going even further, many platforms allow a file to be >>> mapped into an >>>application's address space. I work with an unmanaged C++ Windows >>>application that does CreateFile() to open a file,
>> Binyamin Dissen wrote: You are referring to a LDS. > Paul Raulerson wrote: Like a Master Catalog? Yep- same kind of idea. More > widely used under *nix I think. This demonstrates the biggest flaw in Unix and how detrimental this mentality can be. Unix is about what I must know and MVS is not being aware of. Think about the terms "do anything he wants to optimize" and "more widely used". This bugs me more than the problems we discussed with C. It's great that Eric was able to use createfile for instorage files. As a programmer, it's great that he code whatever he feels makes his program great (in this case optimize). Is this in the business's best interest? Unix programmers can tell you about thousands of features that are "more widely used on *nix". These features are widely known and the programmers can easily implement in their program. Are they really implementing in the business's best interest? MVS programmers are in awe when they hear about these Unix features and will quickly tell a Unix programmer they wish they had that (e.g. createfile). MVS programmers are often totally unaware that these features exist or when they are using them. Case in point is Unix createfile. As Binyamin stated, one of the MVS equivalents would be LDS. There is not a single programmer that knows about (or has any need to know about) LDS. I hear "more widely used" so often. How can anyone guess stats about features that are so well hidden. Ask any MVS programmer about the actual file used in their program (QSAM, BSAM, KSDS, RRDS, ESDS, LDS, RECFM, LRECL, BLKSIZE, Local shared resources and ...). They may make a guess but it could easily be wrong. Without changing their programs, the data could be QSAM and tomorrow VSAM. A cobol programmer that has "file access is key" would say it must be KSDS but they could be wrong. MVS has subsystem datasets where developers can provide data from any source as a file. They are only limited by their imagination (e.g. random number generator, TCP, database or ???) IBM (B stands for business) focuses on the business's best interest. Look at all the features we hide from programmers. Recovery of a file (HSM), disk full (HSM), "The Cloud" functionality (CICS, IMS, shared dasd, JES, ...). Programmers get so much functionality with a small learning curve. More time to keep up on their area of expertise. Unix is a case of motivated reasoning. People want to use it because they get to do so much (e.g. createfile). Other than $$$$, how could any business justify choosing Unix over MVS. $$$$ is usually the deciding factor but you get what you pay for. Regards, Jon.
