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Hello everyone, I'm trying to split the C source code of one file into nearly 10 different. It does not work properly due to global variables declared in one header file but used in more than one C files. Compiling of such a project works fine but the linking errors L104 and L118 occur. My question: How can I prevent this errors without creating one header file for every C file? My idea is the following, but it is complicated and additionally unsure if it works:
#ifdef CPVAR extern unsigned char global_var1; extern unsigned int global_var2; extern unsigned long global_var3; #elseif unsigned char global_var1; unsigned int global_var2; unsigned long global_var3; #define CPVAR #endif
erik, Wow... I guess I totally missed your point. My apologies. Yes, I think when you use that particular method, that things end up being fairly readable, and I personally like it better than having global variables smattered at the top of each C file. Nonetheless, I do find that things I write tend to devolve into ugliness when I'm doing C51 code with this method. For instance, I almost always need to have some variables located with the _at_ keyword, which leads to the following sort of construct:
#ifdef DEFINEGLOBALSHERE #define GLOBAL unsigned char somespecialvar _at_ 0x0200; #else #define GLOBAL extern extern unsigned char somespecialvar; #endif GLOBAL unsigned char somenormalvar;
Take a look at the following knowledgebase article for several other ideas about how to do this: http://www.keil.com/support/docs/1868.htm Jon
Problem is solved. Thank you guys!
"Managing software engineers is like trying to herd cats" -Anonymous silicon valley manager
"Managing software engineers is like trying to herd cats" But what if the result is the cat's miauw? Erik