Why these original FORTRAN quirks?
in [Fortran]
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From: blmblm@myrealbox.com on 23 Nov 2006 08:00 In article <ehstlj$8qk_005(a)s834.apx1.sbo.ma.dialup.rcn.com>, <jmfbahciv(a)aol.com> wrote: > In article <1161796701.620075.134910(a)k70g2000cwa.googlegroups.com>, > wclodius(a)lanl.gov wrote: > > > >Gene Wirchenko wrote: > >> nospam(a)see.signature (Richard E Maine) wrote: > >> > >> >Rostyslaw J. Lewyckyj <urjlew(a)bellsouth.net> wrote: > >> > >> [snip] > >> > >> >> purely Fortran? But I'd consider that to be rather unrealistic in a > >> >> production environment. Linkers, loaders, libraries etc. are a fact > >> >> of life. > >> > > >> >I think we are not communicating here. The linkers, loaders, etc, are > >> >part of the Fortran environment. That's why the Fortran standard (like > >> > >> They are? I used FORTRAN, back in the capitals days. The linker > >> and loader were part of the OS. Many language systems used them. > > > >Of course they are part of the Fortran environment. They were also part > >of the environment of any other language system that relied on them. A > >(viable) (fortran) compiler must (be designed to) deal with their > >conditions and influences (it is in effect surrounded by them) and the > >result of using the linkers and loaders must be a code that must be be > >usable within the system (including the OS) it is used in. > > CAreful. The linkers and loaders aren't separate. What is even > worse is that the kiddies who think they know how machines work, > are not aware of the reasons for linkers and loaders; they assume, > rightly from their experience, that it is all one procedural step. > This is a loss of knowledge that is happening right now. It might be worse than you think: I'm not even sure they all really understand that compiling has to happen (well, assuming a compiled rather than an interpreted language). Tools such as Eclipse (an IDE -- Interactive Development Environment, more on request) compile on the fly as the user types (presumably so they can more or less flag errors as they're typed) and/or automatically when the user clicks the "run" button. I suspect this makes it easy to not realize that this important step is happening. -- B. L. Massingill ObDisclaimer: I don't speak for my employers; they return the favor.
From: blmblm@myrealbox.com on 23 Nov 2006 08:10 In article <ei271h$8qk_001(a)s765.apx1.sbo.ma.dialup.rcn.com>, <jmfbahciv(a)aol.com> wrote: > In article <1162080057.213334.46970(a)f16g2000cwb.googlegroups.com>, > "Terence" <tbwright(a)cantv.net> wrote: [ snip ] > >Bill Gates spotted the software market future and IBM didn't; but the > >costs of using Fortran for any scientific work are becoming ridiculous. > > <snip> > > What lanugage do you think scientists use instead of FORTRAN? Belatedly chiming in to add a data point: The scientist in the office next to mine (well, I think I can call him that even though he works for an academic CS department, since he has a PhD in a "real science" and works on large astrophysics simulations?) mostly uses C++ and Java (with the Java getting more use to write companion tools, e.g., for plotting stuff). IIRC, when he was in grad school he thought about teaching himself Fortran 9x so he could adapt and extend some old Fortran/FORTRAN code, but at the time Fortran 9x compilers weren't sufficiently mature to give good-performing code if the "new" features were used. So he stuck with C++ (which he'd presumably learned from doing a lot of academic CS as well). There was a recent post in -- comp.lang.fortran I think -- by Richard Maine in which he said (IIRC) that somewhere in NASA you could probably find someone using just about any <something> language. > I know of one site that is willing to spend $50K/year(est.) for > a language because the development and support and agility to > do the computer work the scientists need is worth it. -- B. L. Massingill ObDisclaimer: I don't speak for my employers; they return the favor.
From: Brian Inglis on 23 Nov 2006 09:19 On 23 Nov 2006 12:47:17 GMT in alt.folklore.computers, blmblm(a)myrealbox.com <blmblm(a)myrealbox.com> wrote: >In article <4564B1BC.6D607D07(a)yahoo.com>, >CBFalconer <cbfalconer(a)maineline.net> wrote: >> Charlie Gibbs wrote: >> > jmfbahciv(a)aol.com (jmfbahciv) writes: >> > >> >> And didn't IBM develop a philosophy of nailing down physical >> >> addresses before anything can get started? This makes sense >> >> if your sysetm is a data processing production system. You do >> >> not want to start a job that needed a resource which doesn't exist >> >> before the job is started. >> >> >> >> I'm not saying this is "wrong". I'm saying that it's a different >> >> approach that has different side effects than waiting until >> >> the second the resource is needed to provide it. >> > >> > Indeed. It's even possible to get into resource allocation deadlocks >> > if you don't have everything reserved ahead of time. In a mindset >> > that insists that a job make it to completion once it's started, the >> > trade-offs are a bit different. (Mind you, few people understand >> > such a mindset these days - thanks to Microsoft, crashes and forced >> > cancellations are accepted as normal.) >> >> IIRC it is sufficient to describe all non-shareable resources by an >> integer, and insist on accessing those in strictly increasing >> numerical descriptions, while releasing them in the inverse order. >> > >IIRC you are right that if you give every resource a unique number >and access them in strictly increasing order deadlock is impossible. >But I don't think there are any restrictions on the order in which >things are released. (Now someone can correct me if I'm wrong. :-)? ) Ideally, you want to reserve and release all resources as a set. -- Thanks. Take care, Brian Inglis Calgary, Alberta, Canada Brian.Inglis(a)CSi.com (Brian[dot]Inglis{at}SystematicSW[dot]ab[dot]ca) fake address use address above to reply
From: Peter Flass on 23 Nov 2006 09:56 Anne & Lynn Wheeler wrote: > > my complaints with the os/360 convention wasn't particularly the > resolving ... it was that the convention had the relocation address > constants distributed thruout the executable image. I think TSS collected them all into one segment. >
From: Peter Flass on 23 Nov 2006 09:58
Anne & Lynn Wheeler wrote: that caused > problems when i did paged mapped filesystem for cms in the early 70s, > it wasn't possible to just page map the executable image and then > start execution ... the executable image had to be page mapped and > then the linker/loader had to run thru (essentially) random locations > in the executable image .... swizzling the relocatable address > constants. this requires that some (nearly random) number of pages > have to be prefetched by the link/loader and modified (before > application execution can be begin). Sorry, I missed this in my last post, why not just page-map the executable and tag the pages. You could do the relocation withing a page the first time it was referenced? |