true(1) — Commands
NAME
true, false − Returns a standard exit value
SYNOPSIS
true
false
STANDARDS
Interfaces documented on this reference page conform to industry standards as follows:
false: XPG4, XPG4−UNIX
true: XPG4, XPG4−UNIX
Refer to the standards(5) reference page for more information about industry standards and associated tags.
DESCRIPTION
The true command returns a 0 (zero) exit value. The false command returns a nonzero exit value. These commands are usually used in input to shell commands.
EXAMPLES
To construct a loop in a shell procedure, enter:
while true
do
date
sleep 60
done
This procedure displays the date and time once a minute. To stop it, press the Interrupt key sequence.
NOTES
The special built-in utility : (colon) is sometimes more efficient than the true command.
EXIT VALUES
[Digital] The nonzero value returned by the false command may vary from system to system.
RELATED INFORMATION
Commands: csh(1), ksh(1), Bourne shell sh(1b), POSIX shell sh(1p)