How to print signed hexadecimal in C

Question

I know we can use printf("%04X", value); to print unsigned hexadecimal values.

Is there a similar flag or a function in C that you can use to print signed hex values?

Something similar like this

Binary   Hex (signed) Hex (unsigned)
-------- ----------- --------------

00000010 +0x2        0x2
00000001 +0x1        0x1
00000000 +0x0        0x0
11111111 -0x1        0xFF
11111110 -0x2        0xFE
11111101 -0x3        0xFD

Answer 1

Unfortunately C's printf function has no way to do this directly. You could of course instead try:

printf("%s%x\n", x<0 ? "-" : "", x<0 ? -(unsigned)x : x);

This should also work for handling INT_MIN.

Answer 2

No, but you can do something like

printf("%c%04X", (x<0) ? '-' : ' ', (x<0) ?-x : x);

But, as other point out, it is doubtful whether there is a valid reason to do so. According to your post, you do understand what you're asking for, so it's all your fault ;-)