Question

I want to take the value stored in a 32 bit unsigned int, put it into four chars and then store the integer value of each of these chars in a string.

I think the first part goes like this:

char a = orig << 8; char b = orig << 8; char c = orig << 8; char d = orig << 8; 

Answer 1

If you really want to extract the individual bytes first:

unsigned char a = orig & 0xff; unsigned char b = (orig >> 8) & 0xff; unsigned char c = (orig >> 16) & 0xff; unsigned char d = (orig >> 24) & 0xff; 

Or:

unsigned char *chars = (unsigned char *)(&orig); unsigned char a = chars[0]; unsigned char b = chars[1]; unsigned char c = chars[2]; unsigned char d = chars[3]; 

Or use a union of an unsigned long and four chars:

union charSplitter {     struct {         unsigned char a, b, c, d;     } charValues;      unsigned int intValue; };  charSplitter splitter; splitter.intValue = orig; // splitter.charValues.a will give you first byte etc. 

Update: as friol pointed out, solutions 2 and 3 are not endianness-agnostic; which bytes a, b, c and d represent depend on the CPU architecture.