You can only have one flexible array member in a struct, and it must always be the last member of the struct. In other words, in this case you’ve gone wrong before you call malloc, to the point that there’s really no way to call malloc correctly for this struct. To do what you seem to want (arrays … Read more
Answer: sizeof returns the size of the type in bytes. Example: sizeof(char) is 100% guaranteed to be 1, but this does not mean, that it’s one octet (8 bits). Proved by the standard: in 6.5.3.4, point 2: The sizeof operator yields the size (in bytes) of its operand, which may be an expression or the parenthesized name of a type. The … Read more
declares ptr a pointer to const int type. You can modify ptr itself but the object pointed to by ptr shall not be modified. While declares ptr a const pointer to int type. You are not allowed to modify ptr but the object pointed to by ptr can be modified. Generally I would prefer the declaration like this which make it easy to read and understand (read from right to left):
Don’t define variables in headers. Put declarations in header and definitions in one of the .c files. In config.h In some .c file: If you put a definition of a global variable in a header file, then this definition will go to every .c file that includes this header, and you will get multiple definition … Read more
You got nested loop with do/while. Make sure that each start with do end with while. Look like at the end of file, the “while” is not correct. That could be you missing the close ‘}’ before ‘while (rows <= height);’ Correct code could be:
Your use of strlen() is wrong, that is reliant on the contents of the buffer being a valid string; it doesn’t clear the entire buffer. Just use memset() with sizeof: Note that sizeof is not a function, so no parentheses are needed (or should be used, in my opinion) for cases like these. If your C library doesn’t include memset(), a plain loop … Read more
The code posted is incorrect: a_static and b_static should be defined as arrays. There are two ways to correct the code: you can add null terminators to make these arrays proper C strings: Alternately, printf can print the contents of an array that is not null terminated using the precision field: The precision given after the . specifies the maximum number of characters … Read more
malloc is used for dynamic memory allocation. As said, it is dynamic allocation which means you allocate the memory at run time. For example when you don’t know the amount of memory during compile time. One example should clear this. Say you know there will be maximum 20 students. So you can create an array with … Read more
Have a look at this picture: Graphical Projections The glOrtho command produces an “Oblique” projection that you see in the bottom row. No matter how far away vertexes are in the z direction, they will not recede into the distance. I use glOrtho every time I need to do 2D graphics in OpenGL (such as health bars, menus … Read more
So many problems in so few lines. I probably forget some: argv[0] is the program name, not the first argument; if you want to read in a variable, you have to allocate its memory one never loops on feof, one loops on an IO function until it fails, feof then serves to determinate the reason … Read more