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TRUE(1P)                   POSIX Programmer's Manual                  TRUE(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
       true - return true value
SYNOPSIS
       true
DESCRIPTION
       The true utility shall return with exit code zero.
OPTIONS
       None.
OPERANDS
       None.
STDIN
       Not used.
INPUT FILES
       None.
ENVIRONMENT VARIABLES
       None.
ASYNCHRONOUS EVENTS
       Default.
STDOUT
       Not used.
STDERR
       Not used.
OUTPUT FILES
       None.
EXTENDED DESCRIPTION
       None.
EXIT STATUS
       Zero.
CONSEQUENCES OF ERRORS
       None.
       The following sections are informative.
APPLICATION USAGE
       This utility is typically used in shell scripts, as shown in the  EXAM-
       PLES  section.  The  special built-in utility : is sometimes more effi-
       cient than true.
EXAMPLES
       This command is executed forever:

              while true
              do
                  command
              done
RATIONALE
       The   true   utility   has   been   retained   in   this   volume    of
       IEEE Std 1003.1-2001, even though the shell special built-in : provides
       similar functionality,  because  true  is  widely  used  in  historical
       scripts and is less cryptic to novice script readers.
FUTURE DIRECTIONS
       None.
SEE ALSO
       false, Shell Commands
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                             TRUE(1P)