Интерактивная система просмотра системных руководств (man-ов)
true (1)
true (1) ( Solaris man: Команды и прикладные программы пользовательского уровня )
true (1) ( FreeBSD man: Команды и прикладные программы пользовательского уровня )
true (1) ( Русские man: Команды и прикладные программы пользовательского уровня )
true (1) ( Linux man: Команды и прикладные программы пользовательского уровня )
>> true (1) ( POSIX man: Команды и прикладные программы пользовательского уровня )
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 EXAMPLES
section. The special built-in utility : is
sometimes more efficient than true.
EXAMPLES
This command is executed forever:
while true
do
command
done
RATIONALE
The true utility has been retained in this volume of IEEE Std 1003.1-2001,
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
false , Shell Commands
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group. 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.opengroup.org/unix/online.html .
