Programming Tools Guide
Chapter 3, C language compiler
Iteration statements
Iteration statements
while
while (expression)
statement
This sequence is followed repetitively:
-
expression is evaluated.
-
If expression is non-zero, statement is executed.
-
If expression is zero, statement is not executed,
and the repetition stops.
expression
must have scalar type.
do-while
do
statement
while (expression);
This sequence is followed repetitively:
-
statement is executed.
-
expression
is evaluated.
-
If
expression
is zero, repetition stops.
(do-while tests loop at the bottom;
while tests loop at the top.)
for
for (expression1; expression2; expression3)
statement
-
expression1 initializes the loop.
-
expression2 is tested before each iteration.
-
If expression2 is true:
-
statement is executed.
-
expression3 is evaluated.
-
Loop until expression2 is false (zero).
-
Any of expression1, expression2,
or expression3 may be omitted, but
not the semicolons.
-
expression1
and
expression3
may have any type;
expression2
must have scalar type.