32 keywords defined by the C language standard

Keyword meaning

Auto declares automatic variables, by default the compiler generally defaults to auto

int declares an integral type variable

Double declares a dual-precision variable

Long declares a variable of length integer

float declares floating-point variables

Short declares the variable

Signed declaring a signed type variable

Unsigned declaring unsigned integer variables

struct declares struct-body variable

Union Declaration Union data type

Enum Declaration enum type

Static variable declaration

Switch for switching statements

Case Switch Statement Branch

The "other" branch in the default switch statement

Const declares read-only variables

Volatile explanatory variables can be implicitly changed in the program

typedef is used to alias data types (and of course other functions)

extern declaration variables are declared in other files (and can also be considered reference variables)

Return subroutine returns statement (with or without parameters)

void declaration function has no return value or no parameter, declares null type pointer

Contitue end the current loop and start the next cycle

Loop body of Do Loop statement

The loop condition of the while loop statement

If condition statement

Else conditional Statement Negation branch (with IF)

For a loop statement (imaginative achievement here inexpressible)

Goto Unconditional Jump Statement

sizeof calculates the amount of memory space the object occupies

32 keywords defined by the C language standard