1TRUE(1P)                   POSIX Programmer's Manual                  TRUE(1P)
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PROLOG

6       This  manual  page is part of the POSIX Programmer's Manual.  The Linux
7       implementation of this interface may differ (consult the  corresponding
8       Linux  manual page for details of Linux behavior), or the interface may
9       not be implemented on Linux.
10

NAME

12       true - return true value
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SYNOPSIS

15       true
16

DESCRIPTION

18       The true utility shall return with exit code zero.
19

OPTIONS

21       None.
22

OPERANDS

24       None.
25

STDIN

27       Not used.
28

INPUT FILES

30       None.
31

ENVIRONMENT VARIABLES

33       None.
34

ASYNCHRONOUS EVENTS

36       Default.
37

STDOUT

39       Not used.
40

STDERR

42       Not used.
43

OUTPUT FILES

45       None.
46

EXTENDED DESCRIPTION

48       None.
49

EXIT STATUS

51       Zero.
52

CONSEQUENCES OF ERRORS

54       None.
55
56       The following sections are informative.
57

APPLICATION USAGE

59       This utility is typically used in shell scripts, as shown in the  EXAM‐
60       PLES  section.  The  special built-in utility : is sometimes more effi‐
61       cient than true.
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EXAMPLES

64       This command is executed forever:
65
66
67              while true
68              do
69                  command
70              done
71

RATIONALE

73       The   true   utility   has   been   retained   in   this   volume    of
74       IEEE Std 1003.1-2001, even though the shell special built-in : provides
75       similar functionality,  because  true  is  widely  used  in  historical
76       scripts and is less cryptic to novice script readers.
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FUTURE DIRECTIONS

79       None.
80

SEE ALSO

82       false, Shell Commands
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85       Portions  of  this text are reprinted and reproduced in electronic form
86       from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
87       --  Portable  Operating  System  Interface (POSIX), The Open Group Base
88       Specifications Issue 6, Copyright (C) 2001-2003  by  the  Institute  of
89       Electrical  and  Electronics  Engineers, Inc and The Open Group. In the
90       event of any discrepancy between this version and the original IEEE and
91       The  Open Group Standard, the original IEEE and The Open Group Standard
92       is the referee document. The original Standard can be  obtained  online
93       at http://www.opengroup.org/unix/online.html .
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97IEEE/The Open Group                  2003                             TRUE(1P)
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