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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 "$i"
           then break
           fi
       done
RATIONALE
       In  early proposals, consideration was given to expanding the syntax of
       break and continue to refer to a label associated with the  appropriate
       loop  as a preferable alternative to the n method. However, this volume
       of POSIX.1-2008 does reserve the name space  of  command  names  ending
       with  a  <colon>.  It is anticipated that a future implementation could
       take advantage of this and provide something like:
           outofloop: for i in a b c d e
           do
               for j in 0 1 2 3 4 5 6 7 8 9
               do
                   if test -r "${i}${j}"
                   then break outofloop
                   fi
               done
           done
       and that this might be standardized after implementation experience  is
       achieved.
FUTURE DIRECTIONS
       None.
SEE ALSO
       Section 2.14, Special Built-In Utilities
COPYRIGHT
       Portions  of  this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology
       --  Portable  Operating  System  Interface (POSIX), The Open Group Base
       Specifications Issue 7, Copyright (C) 2013 by the Institute of Electri-
       cal  and  Electronics  Engineers,  Inc  and  The  Open Group.  (This is
       POSIX.1-2008 with the 2013 Technical Corrigendum  1  applied.)  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.unix.org/online.html .
       Any typographical or formatting errors that appear  in  this  page  are
       most likely to have been introduced during the conversion of the source
       files to man page format. To report such errors,  see  https://www.ker-
       nel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group                  2013                            BREAK(1P)