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extern 11 Years Ago by Suzie999 … can not do that, and use global variables and the extern keyword which works fine. However, I am at a point… there a similar method for functions as there is with extern keywaod for variables. I know my project might not have… Re: extern 11 Years Ago by rubberman Like declaring global variables as extern, you can do that with functions as well. Here is an example from a header file in my current work project: `extern int setup_notify_events();` Re: extern 11 Years Ago by mike_2000_17 @rubberman: using just `extern` in front of a function declaration in C/C++ has … declarations declare functions with external linkage by default, adding the `extern` keyword doesn't change anything. @Suzie999: You need to provide… Re: extern 11 Years Ago by Moschops … a half decent fashion. Your use of global variables and extern is the nasty hacky version. What I did above is… Re: extern 11 Years Ago by DeanMSands3 … about a nice example? //moo.h #include <string> extern std::string moo; //Declare the variable externally without actually creating… extern or compiler directive problem 7 Years Ago by Thomas_36 … "bull.h" int po(int x) { extern std::string DRIVE; std::cout << DRIVE <… I wrote these files to learn about the extern command used with global variables defined in a different… Finally, back to learning about global variables and extern, I tried to intialize the variable DRIVE in the… extern, xdebug, ctype.h 14 Years Ago by sblass92 … "unit.h" extern std::vector <unit> reserved_units; extern std::list <unit*> active; extern std::vector <unit…: 'unit" : undeclared identifier errors, a syntax error '>' for extern std::list <unit*> active; and then what is… extern variable 14 Years Ago by xaop …is to write a program to illustrate external storage class, extern variable,global variable and thus write the differences between global… variable. My program : [CODE]#include <stdio.h> extern int i; int main() { printf("\n%d",i… mistake in the program and in the usage of extern variable. Thanks a lot for your time. Re: Extern reference to a variable name of different type 14 Years Ago by Ancient Dragon … be declared later. It's common to declare variables using extern in header files. Then in one, and only one *.c… variable(s) have to be declared again but without the extern keyword. The compiler does not complain about the difference between… Re: Extern reference to a variable name of different type 14 Years Ago by swapnaoe /*main.c*/ extern int f(void); main() { f(); getchar(); } /*file1.c*/ …although the compiler is unaware of the definition of extern function, how about the linker knowing it and…? signature of object(func or variable) during declaration(extern) and during definition can be different provided name is… extern function link error 2005 15 Years Ago by thriek …; function called wait(), defined it in a header file with extern keyword, and then in the main file prototyped it and… included in other files... halp plz? [CODE] //header file definition extern void wait(void) { char c = getchar(); while (c != '\n') c… Extern reference to a variable name of different type 14 Years Ago by swapnaoe [CODE=c] /*main.c*/ #include<stdio.h> extern void func(void); main() { extern int i; printf("i in main %d… Re: extern variable 14 Years Ago by GuitarComet The extern keyword tells the compiler that the symbol (in this case i) is located in an external module. In simple words, in another source file. In another source file, declare the variable i as you normally would declare a global variable. extern "C" not working? 11 Years Ago by daProgramma … am not able to stop the name mangling.I have extern "C" __declspec(dllexport) int __stdcall add( int a… course, but thats not very readable. Question: why does the extern "C" does not have any effect here? Thank… Re: extern "C" not working? 11 Years Ago by daProgramma Sure did I read this, and many other articles. Did you read it too? To my understanding it says one should use 'extern "C"' what my code seems to have. Extern, Classes and Includes 15 Years Ago by Lothas ….cpp [CODE]#include "GLCursor.h" // ---> Window Parameters extern FLGLWindow GL_MainWin; ....[/CODE] FLGLWindow.h [CODE]// FLGLWindow.h: interface for… Extern Functions: 15 Years Ago by tatyakadam …); return x+y; } ----------------------------------- Simple2.c ------------------------------------ #include<stdio.h> extern int f1(int x,int y); void main() { printf("… extern struct in header file 14 Years Ago by kiwihaha … <cstdlib> #include <iostream> using namespace std; extern car c; class test{ c.year=10;}; [/CODE] Re: Please help me with EXTERN usage 17 Years Ago by WaltP … to be accessible from a another source file. Add the EXTERN statement in a local header file and define the variable… = 0;[/inlinecode] In [I]error.h[/I] you define [inlinecode]extern int errCode;[/inlinecode] and [inlinecode]#include[/inlinecode] this file in… Re: extern 11 Years Ago by Moschops I struggle to think what you have done with your code if you are unable to use a function that has been written in a different cpp file. So long as the cpp file you want to use it in has seen the prototype of that function (which is usually done with a header file), when time comes to link the code together, the linker will find that other function… Re: extern 11 Years Ago by Suzie999 It's a mess I know. This is my first attempt at bringing all the code together, and it will be re-thought and designed when I look at the whole thing working. What needs this new function a added is a class member, where the method is defined inside the class in the class.h file. From my search about this problem I read I should #include "… Re: extern 11 Years Ago by Suzie999 Thank you all for your replies, helped me to realise a very simple solution, to just put the extra function into its own cpp and h files and include it before all other includes. I really appreciate your time Thank you. Re: How does extern const work? 12 Years Ago by mike_2000_17 …. > And for other non-const variables, it is extern by default, right? Yes. Unless they appear in an anonymous… namespace. > Why must the extern keyword be mentioned twice, once in the header and once…variable, how will it matter to it, whether it is extern or not? Because the compiler must generate compiled code (… what does it mean? "extern ... **d" 13 Years Ago by sajaddehghan I don't know what the "*" or "**"or "***" means. could anyone help me please? [CODE] #include <iostream.h> #include <complex.h> #define PI 3.141592654 extern int phin,Ne; extern double Lamda; extern double ***TS; extern double ***TF; extern complex **d; extern complex *bd;[/CODE] Why storage class auto,extern,static not alloed in function parameter 12 Years Ago by sachi059 ….But it gives error when i mae it extern auto,extern static... Hello i found that only register storage… function.But it gives error when i mae it extern auto,extern static... #include<stdio.h> int sum…quot;,d); } int sum(static int a,register int b,extern int c) { return a+b+c; } int c… How to change the value of extern variable 13 Years Ago by peuceul … all, I have a question regarding an extern variable. ---test.c [CODE]#include <…include </home/peuceul/debug/test.h> extern int a; int print1() { printf("value… of a in extern is %d\n", a); int a …am trying to change the value of an extern variable(mainly int a) using print1 method… Re: How exactly to use extern? 16 Years Ago by Ancient Dragon The [b]extern[/b] keyword is used to tell the compiler that…code] // A.cpp #include <iostream> // other includes here ... extern int hours; // this is declared globally in B.cpp int… here ... int hours; // here we declare the object WITHOUT extern extern void foo(); // extern is optional on this line int main() { foo(); } … Re: How does extern const work? 12 Years Ago by theguitarist … the "constants.cpp", you need to write: > extern const int var = 5; > This is because, by default… form a translation unit. Lets say I didn't use `extern`. It becomes `static` by default. So when I now include… variable, how will it matter to it, whether it is extern or not? After all, the linking happens later, and the… Please help me with EXTERN usage 17 Years Ago by Ratte … a file of 14 functions. I know I need an extern array of 14 bools. If something goes wrong in one… easier other ways, but I have to do it with extern and I cannot get the linkage to work because I…; } [/code] Any tips on where and how I declare the extern variable would be greatly appreciated. Help with header files, declaring extern vars 17 Years Ago by Barefootsanders … Its giving me an error when i do this [CODE]extern void mainMenu(node*);[/CODE] Now node is a struct defined… header file, should I include that as an extern variable as well? Something like extern struct node; ?? Thanks for the help in…