true(1p) - phpMan

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 POSIX.1-2008, 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
       Section 2.9, Shell Commands, false
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                             TRUE(1P)