Disable structure padding in C without using pragma

Question

How can I disable structure padding in C without using pragma?

Answer 1

Either you let compiler do padding, or tell it not to do using #pragma, either you just use some bunch of bytes like a char array, and you build all your data by yourself (shifting and adding bytes). This is really inefficient but you'll exactly control the layout of the bytes. I did that sometimes preparing network packets by hand, but in most case it's a bad idea, even if it's standard.