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Hi Luis
The general goal I was aiming for was to be able to use luac to compile a lua binary on a PC (the typical development environment) and be able to run that on different embedded hardware. I was pondering what is involved to achieve that ? Just the large number of devices around these days means there is bound to be a mix of Endian's. I would say Little Endian is the most common, but for example the Wii, and the PS3 are Big Endian I think. > And these are the only differences between them?? No I didnt mean that, there are bound to be lots of different hardware configurations. But lets consider where hardware differences impact Lua ? 1) Filesystems: In my experience filesystems typically look like the ANSI libary, fopen(), fclose(), fread() etc. 2) I/O Systems: For embedded systems this usually just redirects the C printf() to a Serial Port, or maybe a console screen if one is available. 3) Real Time Clock: This probably boils down to a just a couple of functions to read and write to the hardware. Porting Lua for the above 3 points is fairly straightforward and someone coming at Lua for the first time would have a reasonable understanding of what is needed to be done, and the size of the work involved. What isnt straightforward, and a new Lua user wouldnt have a clue how to do or the size of the task, is how to tackle the Endianism problem ? Thats why I was saying it would be good to restore the old endianism agnostic feature it used to have back in its early days. I was very pleasantly surprised when you posted your 1996 patch to fix the endian problem and I discovered how minimal the changes were. (and still worked fine in 2011) Geoff > From: lhf@tecgraf.puc-rio.br > To: lua-l@lists.lua.org > Subject: Re: Can someone sell Lua 5.2.0 to me please ? > > > now we are nearly in 2012 with a plethora of consoles, hand helds, > > tablets etc, this issue of being endian agnostic is very much more > > useful than it would have been back in back in the late 90's whenever > > the decision was taken to remove the feature. > > Are you saying that all those devices have different endianness? > And these are the only differences between them?? > > Or that you'd rather generate one precompiled file and run it everywhere? > > In this case, I think what you need is a cross-compiler, ie, a version > of luac that outputs in the correct order for each platform. > > I assume there is a separate build process for each platform anyway. > So this luac step would just be one more step in that process. > |