The header file <stdio.h> defines a number of functions to format and output values. The format-control directives that for the formatted input and output function are described in Formatted input control strings and Formatted output control strings.

Character and string I/O functions
getchar | Read a character from standard input
gets | Read a string from standard input
putchar | Write a character to standard output
puts | Write a string to standard output
Formatted input functions
scanf | Read formatted text from standard input
sscanf | Read formatted text from a string
vscanf | Read formatted text from standard input using a va_list argument
vsscanf | Read formatted text from a string using a va_list argument
Formatted output functions
printf | Write formatted text to standard output
snprintf | Write formatted text to a string with truncation
sprintf | Write formatted text to a string
vprintf | Write formatted text to standard output using a va_list argument
vsnprintf | Write formatted text to a string with truncation using a va_list argument
vsprintf | Write formatted text to a string using a va_list argument