optimization - What are some best practices for reducing memory usage in C?

Question

What are some best practice for "Memory Efficient C programming". Mostly for embedded/mobile device what should be the guidelines for having low memory consumptions ?

I guess there should be separate guideline for a) code memory b) data memory

Answer 1

In C, at a much simpler level, consider the following;

• Use #pragma pack(1) to byte align your structures
• Use unions where a structure can contain different types of data
• Use bit fields rather than ints to store flags and small integers
• Avoid using fixed length character arrays to store strings, implement a string pool and use pointers.
• Where storing references to an enumerated string list, e.g. font name, store an index into the list rather than the string
• When using dynamic memory allocation, compute the number of elements required in advance to avoid reallocs.