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Linux 2.6 - man page for break (linux section 1)

BREAK(P)						     POSIX Programmer's Manual							  BREAK(P)

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 speci- fied. 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 "$i" then break fi done
RATIONALE
In early proposals, consideration was given to expanding the syntax of break and continue to refer to a label associated with the appropri- ate loop as a preferable alternative to the n method. However, this volume of IEEE Std 1003.1-2001 does reserve the name space of command names ending with a colon. It is anticipated that a future implementation could take advantage of this and provide something like: outofloop: for i in a b c d e do for j in 0 1 2 3 4 5 6 7 8 9 do if test -r "${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
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technol- ogy -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html .
IEEE
/The Open Group 2003 BREAK(P)