'\" te
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.TH let 1 "2 Nov 2007" "SunOS 5.11" "User Commands"
.SH NAME
let \- shell built-in function to evaluate one or more arithmetic expressions
.SH SYNOPSIS
.SS "ksh"
.LP
.nf
\fBlet\fR \fIarg\fR...
.fi

.SS "ksh93"
.LP
.nf
\fBlet\fR [\fIexpr\fR...]
.fi

.SH DESCRIPTION
.SS "ksh"
.sp
.LP
Each \fIarg\fR is a separate arithmetic expression to be evaluated.
.SS "ksh93"
.sp
.LP
\fBlet\fR evaluates each \fIexpr\fR in the current shell environment as an
arithmetic expression using ANSI C syntax. Variables names are shell variables
and they are recursively evaluated as arithmetic expressions to get numerical
values. \fBlet\fR has been made obsolete by the \fB((...))\fR syntax of
\fBksh93\fR(1) which does not require quoting of the operators to pass them as
command arguments.
.SH EXIT STATUS
.SS "ksh"
.sp
.LP
\fBksh\fR returns the following exit values:
.sp
.ne 2
.mk
.na
\fB\fB0\fR\fR
.ad
.RS 5n
.rt  
The value of the last expression is \fBnon-zero\fR.
.RE

.sp
.ne 2
.mk
.na
\fB\fB1\fR\fR
.ad
.RS 5n
.rt  
The value of the last expression is zero.
.RE

.SS "ksh93"
.sp
.LP
\fBksh93\fR returns the following exit values:
.sp
.ne 2
.mk
.na
\fB\fB0\fR\fR
.ad
.RS 6n
.rt  
The last \fIexpr\fR evaluates to a \fBnon-zero\fR value.
.RE

.sp
.ne 2
.mk
.na
\fB\fB>0\fR\fR
.ad
.RS 6n
.rt  
The last \fIexpr\fR evaluates to \fB0\fR or an error occurred.
.RE

.SH SEE ALSO
.sp
.LP
\fBksh\fR(1), \fBksh93\fR(1), \fBset\fR(1), \fBtypeset\fR(1),
\fBattributes\fR(5)