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
11

NAME

13       true — return true value
14

SYNOPSIS

16       true
17

DESCRIPTION

19       The true utility shall return with exit code zero.
20

OPTIONS

22       None.
23

OPERANDS

25       None.
26

STDIN

28       Not used.
29

INPUT FILES

31       None.
32

ENVIRONMENT VARIABLES

34       None.
35

ASYNCHRONOUS EVENTS

37       Default.
38

STDOUT

40       Not used.
41

STDERR

43       Not used.
44

OUTPUT FILES

46       None.
47

EXTENDED DESCRIPTION

49       None.
50

EXIT STATUS

52       Zero.
53

CONSEQUENCES OF ERRORS

55       None.
56
57       The following sections are informative.
58

APPLICATION USAGE

60       This utility is typically used in shell scripts, as shown in the  EXAM‐
61       PLES  section.  The  special built-in utility : is sometimes more effi‐
62       cient than true.
63

EXAMPLES

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

RATIONALE

73       The true utility has been retained in this volume of POSIX.1‐2008, even
74       though  the  shell  special  built-in : provides similar functionality,
75       because true is widely used in historical scripts and is  less  cryptic
76       to novice script readers.
77

FUTURE DIRECTIONS

79       None.
80

SEE ALSO

82       Section 2.9, Shell Commands, false
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85       Portions  of  this text are reprinted and reproduced in electronic form
86       from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology
87       --  Portable  Operating  System  Interface (POSIX), The Open Group Base
88       Specifications Issue 7, Copyright (C) 2013 by the Institute of Electri‐
89       cal  and  Electronics  Engineers,  Inc  and  The  Open Group.  (This is
90       POSIX.1-2008 with the 2013 Technical Corrigendum  1  applied.)  In  the
91       event of any discrepancy between this version and the original IEEE and
92       The Open Group Standard, the original IEEE and The Open Group  Standard
93       is  the  referee document. The original Standard can be obtained online
94       at http://www.unix.org/online.html .
95
96       Any typographical or formatting errors that appear  in  this  page  are
97       most likely to have been introduced during the conversion of the source
98       files to man page format. To report such errors,  see  https://www.ker‐
99       nel.org/doc/man-pages/reporting_bugs.html .
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103IEEE/The Open Group                  2013                             TRUE(1P)
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