Objective c accessing a global variable from another file [duplicate]

Answer 1

You can use #define number 123 or #define string @"abc" inside the .h and any file that imports it should be able to use the preprocessor name you chose. k is a common prefix for these types of macros as they're in fact constant values.

NOTE: The comments show that there is a difference between using preprocessors you define and actual global variables (with extern declared) though both can be used in separate files by importing the .h file where you declared/defined them.

Answer 2

static variables are declared only once

Answer 3

You can declare variables in .h files.

globals.h:

extern int myGlob;

You cannot define the variable in a .h, You have to define it in a .c or .m:

globals.m:

int myGlob;

You can import globals.h from any other file that needs to access myGlob:

myApp.m:

#import "globals.h"

main() {
    myGlob++;
}