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Variable Visibility

Started by August 17, 2001 11:21 AM
2 comments, last by Prozak 23 years, 6 months ago
Hi all, in msvc++6, cant i put a variable in a header, or in the header''s cpp, so that i can see it in the main file? i cant seem to do this? does anyone remember when they were learning c++, going thru this error? Thanx all, Hugo Ferreira UniteK Future "My Name Is Jerry."[TheSphere]
If I understand what you''re asking, you should use the ''extern'' keyword to tell the compiler that a variable exists, but is defined elsewhere (i.e. in another c/cpp file than the one containing the extern-clause).

Also, remember to never define your variables in header files since that may lead to linker errors and stuff (declaring it extern in a header is ok, as long as it is only *defined* in a single c/cpp file).
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You should never define a variable in a header file. If you do, and that header file is included in 2 files, then you''ll get a linker error. It''s bad practice. You can put extern''s in headers, but that too is sometimes quesitonable.

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Thanx all,

I now see the light, ehheheh

Hugo Ferreira
UniteK Future
"My Name Is Jerry."[TheSphere]



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