7. Libraries

As C is a portable assembler, it does not require a runtime library. This means it can be used to create very small executables with little dependency on an operating system. For example, C can be used to generate programs for embedded processors (washing machines, motor control, etc.).

However, C comes with a "standard library" providing a large number of common functions. These include :

• ctype.h character manipulation (toupper ...) ;

• errno.h error handling (perror ...) ;

• assert.h for focus ;

• locale.h to customize the language and certain displays ;

• math.h for mathematical functions ;

• setjmp.h non-local escapes ;

• ...