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I have many different 3 axis sensors I am writing test code for. In the C files for each of them, I have the same char string defined:
char axis[3][8] = {"X", "Y", "Z"}
which I use when I "for" loop results to print the axis that is failing like this:
DEVICETEST_LOG("%s Failed %s axis for Min range\n",device_name[DUT], axis[i]);
I was thinking to save some space I could define a character string array in a header file to use all over the place.
I have tried a number of things, but I can't seem to get an array of strings defined in my header file that I can iterate through to pass a compile.
419
int array[4] = {1,2,3,4}; will work, but putting objects in headers is generally a bad idea because it is easy to accidentally define the object multiple times just by including the header more than once. Inclusion guards are only a partial fix for that problem.
“array_name = new char[array_length]” is the syntax to be followed. Anyways we can do both declaration and initialization in a single by using “char array_name[] = new char[array_length]” syntax. The length of the array should be declared at the time of initialization in a char array.
char arr[] = {'c','o','d','e','\0'}; In the above declaration/initialization, we have initialized array with a series of character followed by a '\0' (null) byte. The null byte is required as a terminating byte when string is read as a whole.
If you must put it in a header file, use extern or static:
// option 1
// .h
extern char axis[3][8];
// .c
char axis[3][8] = { "X", "Y", "Z" };
// option 2
// .h
static char axis[3][8] = { "X", "Y", "Z" };
Extern tells the linker that there is a global variable named axis defined in one of our implementation files (i.e. in one .c file), and I need to reference that here.
static, on the other hand, tells the compiler the opposite: I need to be able to see and use this variable, but don't export it to the linker, so it can't be referenced by extern or cause naming conflicts.
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