Table 3 Standard C Headers: Group III (power at your fingertips when you need it)

<errno.h>   Error Detection
<float.h>   System Parameters for Real Arithmetic
<locale.h>  Cultural Adaptation
<math.h>    Mathematical Functions
<setjmp.h>  Non-local Branching
<signal.h>  Interrupt Handling (sort of)
<stdarg.h>  Variable-length Argument Lists