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BREAK(1P)                  POSIX Programmer's Manual                 BREAK(1P)

PROLOG
       This  manual  page is part of the POSIX Programmer's Manual.  The Linux
       implementation of this interface may differ (consult the  corresponding
       Linux  manual page for details of Linux behavior), or the interface may
       not be implemented on Linux.
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
COPYRIGHT
       Portions  of  this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
       --  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(1P)