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.TH TRUE "1P" 2013 "IEEE/The Open Group" "POSIX Programmer's Manual"
.SH 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.

.SH NAME
true
\(em return true value
.SH SYNOPSIS
.LP
.nf
true
.fi
.SH DESCRIPTION
The
.IR true
utility shall return with exit code zero.
.SH OPTIONS
None.
.SH OPERANDS
None.
.SH STDIN
Not used.
.SH "INPUT FILES"
None.
.SH "ENVIRONMENT VARIABLES"
None.
.SH "ASYNCHRONOUS EVENTS"
Default.
.SH STDOUT
Not used.
.SH STDERR
Not used.
.SH "OUTPUT FILES"
None.
.SH "EXTENDED DESCRIPTION"
None.
.SH "EXIT STATUS"
Zero.
.SH "CONSEQUENCES OF ERRORS"
None.
.LP
.IR "The following sections are informative."
.SH "APPLICATION USAGE"
This utility is typically used in shell scripts, as shown in the
EXAMPLES section. The special built-in utility
.BR :
is sometimes more efficient than
.IR true .
.SH EXAMPLES
This command is executed forever:
.sp
.RS 4
.nf
\fB
while true
do
    command
done
.fi \fR
.P
.RE
.SH RATIONALE
The
.IR true
utility has been retained in this volume of POSIX.1\(hy2008, even though the shell special
built-in
.BR :
provides similar functionality, because
.IR true
is widely used in historical scripts and is less cryptic to novice
script readers.
.SH "FUTURE DIRECTIONS"
None.
.SH "SEE ALSO"
.IR "Section 2.9" ", " "Shell Commands",
.IR "\fIfalse\fR\^"
.SH 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
Electrical 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.kernel.org/doc/man-pages/reporting_bugs.html .