error: unknown type name ‘bool’
C90 does not support the boolean data type. C99 does include it with this include:
c
Double pointer array in c++
You probably well know that double* is a pointer to a double element. In the same way, double** is a pointer to a double* element, which is itself a pointer. Again, double*** is a pointer to a double** element, and so on. When you instanciate an array to a type T, you usually do new T [size];. For example, for an array of double, you write new double[size];. If your type T is … Read more
Is there any difference between 1U and 1 in C?
On most compliers, both will give a result with the same representation. However, according to the C specification, the result of a bit shift operation on a signed argument gives implementation-defined results, so in theory 1U << i is more portable than 1 << i. In practice all C compilers you’ll ever encounter treat signed left shifts the same … Read more
Are the shift operators (<<, >>) arithmetic or logical in C?
According to K&R 2nd edition the results are implementation-dependent for right shifts of signed values. Wikipedia says that C/C++ ‘usually’ implements an arithmetic shift on signed values. Basically you need to either test your compiler or not rely on it. My VS2008 help for the current MS C++ compiler says that their compiler does an arithmetic shift.
Is there a way to have printf() properly print out an array (of floats, say)?
you need to iterate through the array’s elements or create a function that returns stacked sn printf and then prints it with
What does ** mean in C?
In this case, double means a variable of type double. double* means a pointer to a double variable. double** means a pointer to a pointer to a double variable. In the case of the function you posted, it is used to create a sort of two-dimensional array of doubles. That is, a pointer to an array of double pointers, … Read more
Invalid type argument of -> C structs
a is of type Album* which means that a[i] is of type Album (it is the ith element in the array of Album object pointed to by a). The left operand of -> must be a pointer; the . operator is used if it is not a pointer.
How to parse in C
With a function to read lines from a file, such as get_line (POSIX), or this portable read_line function that I just wrote for this, you can then split the line into tokens using strtok with the delimiter set to “;” (make sure to remove the trailing \n from the line first). You can then copy each token into the relevant array. However, as your file format is … Read more
When to use const char * and when to use const char []
Both are distinctly different, For a start: The First creates a pointer. The second creates an array. Read on for more detailed explanation: The Array version: Creates an array that is large enough to hold the string literal “text”, including its NULL terminator. The array text is initialized with the string literal “text”.The array can be modified at a … Read more
What does the term “empty loop” refer to exactly in C and C++?
Your first case (for with empty expressions) is an infinite loop and the second one (with empty body of the for statement) is an empty loop