break

The Open Group Base Specifications Issue 6
IEEE Std 1003.1, 2004 Edition
Copyright © 2001-2004 The IEEE and The Open Group, All Rights reserved.

#### NAME

> break - exit from for, while, or until loop

#### SYNOPSIS

> ``break` [n]`

#### DESCRIPTION

> The break utility shall exit from the smallest enclosing for, while, or until loop, if any; or from the nth enclosing loop if n is specified. The value of n is an unsigned decimal integer greater than or equal to 1. The default shall be equivalent to n=1. If n is greater than the number of enclosing loops, the outermost enclosing loop shall be exited. Execution shall continue with the command immediately following the loop.

#### OPTIONS

> None.

#### OPERANDS

> See the DESCRIPTION.

#### STDIN

> Not used.

#### INPUT FILES

> None.

#### ENVIRONMENT VARIABLES

> None.

#### ASYNCHRONOUS EVENTS

> Default.

#### STDOUT

> Not used.

#### STDERR

> The standard error shall be used only for diagnostic messages.

#### OUTPUT FILES

> None.

#### EXTENDED DESCRIPTION

> None.

#### EXIT STATUS

> 0
>   Successful completion.
> >0
>   The n value was not an unsigned decimal integer greater than or equal to 1.

#### CONSEQUENCES OF ERRORS

> Default.

The following sections are informative.

#### APPLICATION USAGE

> None.

#### EXAMPLES

>     for i in * do
>         if test -d "$i" then break fi done

#### RATIONALE

> In early proposals, consideration was given to expanding the syntax of break and continue to refer to a label associated with the appropriate loop as a preferable alternative to the n method. However, this volume of IEEE Std 1003.1-2001 does reserve the name space of command names ending with a colon. It is anticipated that a future implementation could take advantage of this and provide something like:

>     outofloop: for i in a b c d e
>     do
>         for j in 0 1 2 3 4 5 6 7 8 9
>         do
>             if test -r "${i}${j}"
>             then break outofloop
>             fi
>         done
>     done

> and that this might be standardized after implementation experience is achieved.

#### FUTURE DIRECTIONS

> None.

#### SEE ALSO

> Special Built-In Utilities

#### CHANGE HISTORY

#### Issue 6

> IEEE Std 1003.1-2001/Cor 1-2002, item XCU/TC1/D6/5 is applied so that the reference page sections use terms as described in the Utility Description Defaults ( Utility Description Defaults ). No change in behavior is intended.

End of informative text.

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