assert.h

Enforcing assertions when functions execute

complex.h

Computing common complex mathematical functions

ctype.h

Classifying characters

errno.h

Testing error codes reported by library functions

fenv.h

Floating-point exception flags

float.h

Testing floating-point type properties

inttypes.h

Defining formatters for all types defined in stdint.h

iso646.h

Alternative spellings

limits.h

Testing integer type properties

locale.h

Adapting to different cultural conventions

math.h

Computing common mathematical functions

setjmp.h

Executing non-local goto statements

signal.h

Controlling various exceptional conditions

stdalign.h

Handling alignment on data objects

stdarg.h

Accessing a varying number of arguments

stdatomic.h

Adding support for atomic operations.

stdbool.h

Adds support for the bool data type in C.

stddef.h

Defining several useful types and macros

stdint.h

Providing integer characteristics

stdio.h

Performing input and output

stdlib.h

Performing a variety of operations

stdnoreturn.h

Adding support for non-returning functions

string.h

Manipulating several kinds of strings

tgmath.h

Type-generic mathematical functions

threads.h

Adding support for multiple threads of execution

This functionality is not supported.

time.h

Converting between various time and date formats

uchar.h

Unicode functionality

wchar.h

Support for wide characters

wctype.h

Classifying wide characters