'\" te
.\"  Copyright 1989 AT&T Copyright (c) 1995, Sun Microsystems, Inc. All Rights Reserved Portions Copyright (c) 1992, X/Open Company Limited All Rights Reserved
.\"  Sun Microsystems, Inc. gratefully acknowledges The Open Group for permission to reproduce portions of its copyrighted documentation.Original documentation from The Open Group can be obtained online at http://www.opengroup.org/bookstore/.
.\" The Institute of Electrical and Electronics Engineers and The Open Group, have given us permission to reprint portions of their documentation.In the following statement, the phrase"this text" refers to portions of the system documentation.Portions of this text are reprinted and reproduced in electronic form in the Sun OS Reference Manual, from IEEE Std 1003.1, 2004 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2004 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group.In the event of any discrepancy between these versions 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.This notice shall appear on any product containing this material. 
.TH true 1 "1995 年 2 月 1 日" "SunOS 5.11" "用户命令"
.SH 名称
true, false \- 提供实际值
.SH 用法概要
.LP
.nf
\fBtrue\fR 
.fi

.LP
.nf
\fBfalse\fR 
.fi

.SH 描述
.sp
.LP
\fBtrue\fR 实用程序不执行任何操作，成功。\fBfalse\fR 实用程序不执行任何操作，不成功。它们在 shell 脚本 \fBsh\fR 中的一般用法如下：
.sp
.in +2
.nf
while true
do
            \fIcommand\fR
done
.fi
.in -2

.sp
.LP
永远执行 \fIcommand\fR。
.SH 退出状态
.sp
.LP
\fBtrue\fR 退出状态为 \fB0\fR。
.sp
.LP
\fBfalse\fR 始终以非零值退出。
.SH 属性
.sp
.LP
有关下列属性的说明，请参见 \fBattributes\fR(5)：
.sp

.sp
.TS
tab() box;
cw(2.75i) |cw(2.75i) 
lw(2.75i) |lw(2.75i) 
.
属性类型属性值
_
可用性system/core-os
_
接口稳定性Committed（已确定）
_
标准请参见 \fBstandards\fR(5)。
.TE

.SH 另请参见
.sp
.LP
\fBsh\fR(1)、\fBattributes\fR(5)、\fBstandards\fR(5)