How to printf "unsigned long" in C?

I can never understand how to print unsigned long datatype in C.

Suppose unsigned_foo is an unsigned long, then I try:

• printf("%lu\n", unsigned_foo)
• printf("%du\n", unsigned_foo)
• printf("%ud\n", unsigned_foo)
• printf("%ll\n", unsigned_foo)
• printf("%ld\n", unsigned_foo)
• printf("%dl\n", unsigned_foo)

And all of them print some kind of -123123123 number instead of unsigned long that I have.

Solution 1:

%lu is the correct format for unsigned long. Sounds like there are other issues at play here, such as memory corruption or an uninitialized variable. Perhaps show us a larger picture?

Solution 2:

For int %d

For long int %ld

For long long int %lld

For unsigned long long int %llu

Solution 3:

• %lu for unsigned long
• %llu for unsigned long long