Null Statement (C)
A "null statement" is a statement containing only a semicolon; it can appear wherever a statement is expected. Nothing happens when a null statement is executed. The correct way to code a null statement is:
Syntax
;
Remarks
Statements such as do
, for
, if
, and while
require that an executable statement appear as the statement body. The null statement satisfies the syntax requirement in cases that do not need a substantive statement body.
As with any other C statement, you can include a label before a null statement. To label an item that is not a statement, such as the closing brace of a compound statement, you can label a null statement and insert it immediately before the item to get the same effect.
This example illustrates the null statement:
for ( i = 0; i < 10; line[i++] = 0 )
;
In this example, the loop expression of the for
statement line[i++] = 0
initializes the first 10 elements of line
to 0. The statement body is a null statement, since no further statements are necessary.