rpaul@crow.UUCP (Rodian Paul) (04/29/91)
I finaly decided to start reading my "Understanding COFF" book by O'Reilly & Associates last week. I found parts to be heavy wading, but decided to plug in their example listings and see what I might learn. The book points out that there are bound to be implementation specific changes/deviations, but the overall COFF structure should be pretty standard. Well, I guess MIPS does diverge more than a little. So I perused the SGI manuals, and the only one that I could find that really deals with object formats is the Assembly Programmers manual. Not being well versed in assembley language, my spirits sagged, thus this e-mail. What I'm particularly interested in is dynamic-loading, i.e. while a program is executing it can run off, compile and/or link an object back into itself, fork and continue running with the extra baggage. This technique would be nice to implement and use in a manner that is used by some Macintosh utilities. Adobe Photoshop and others allow a user to write their own "plug-in" image processing or different file reading/writing filters. An educated user could be supplied with some templates, they then add their own "plug-in's" to a commercial IRIS application, without the need to supply additional libraries. It could also make the process of customization a lot simpler. Anyway, it's something I'd like to mess with. I've heard in the past that under Sys V 3.2, dynamic-loading is a real bitch, but with Sys V 4.0, they've made it much easier. I don't know how much truth there is in that and I realize that it will probably take a while before SGI brings out an IRIX release based on V 4.0. The 99 Yen question? Would some kind soul who has allready figured out dynamic-loading on the SGI/MIPS platform please send me some example code? There seems to be enough support routines ( r.e ldfcn() etc. ) but I can't find any examples in the SGI manuals. Failing source listings, references to any books with examples that don't diverge from the MIPS platform too much would be appreciated just as strongly. Thanks. ------------------------------------------------------------------------------- rpaul%crow@ccut.cc.u-tokyo.ac.jp phone: +81 (3) 5706-8357 ccut.cc.u-tokyo.ac.jp!crow!rpaul FAX: +81 (3) 5706-8437