Module Name: src
Committed By: rillig
Date: Sat Mar 15 16:02:53 UTC 2025
Modified Files:
src/bin/expr: expr.1
Log Message:
expr.1: sync with latest changes, improve wording
To generate a diff of this commit:
cvs rdiff -u -r1.38 -r1.39 src/bin/expr/expr.1
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/bin/expr/expr.1
diff -u src/bin/expr/expr.1:1.38 src/bin/expr/expr.1:1.39
--- src/bin/expr/expr.1:1.38 Sun Aug 28 10:48:16 2022
+++ src/bin/expr/expr.1 Sat Mar 15 16:02:53 2025
@@ -1,6 +1,6 @@
-.\" $NetBSD: expr.1,v 1.38 2022/08/28 10:48:16 hgutch Exp $
+.\" $NetBSD: expr.1,v 1.39 2025/03/15 16:02:53 rillig Exp $
.\"
-.\" Copyright (c) 2000,2003 The NetBSD Foundation, Inc.
+.\" Copyright (c) 2000, 2003, 2025 The NetBSD Foundation, Inc.
.\" All rights reserved.
.\"
.\" This code is derived from software contributed to The NetBSD Foundation
@@ -27,7 +27,7 @@
.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
.\" POSSIBILITY OF SUCH DAMAGE.
.\"
-.Dd August 23, 2016
+.Dd March 15, 2025
.Dt EXPR 1
.Os
.Sh NAME
@@ -35,15 +35,15 @@
.Nd evaluate expression
.Sh SYNOPSIS
.Nm
-.Ar expression
+.Ar operand ...
.Sh DESCRIPTION
The
.Nm
-utility evaluates
-.Ar expression
-and writes the result on standard output.
+utility evaluates the expression consisting of the
+.Ar operand
+arguments and writes the result on standard output.
.Pp
-All operators are separate arguments to the
+Each operand is a separate arguments to the
.Nm
utility.
Characters special to the command interpreter must be escaped.
@@ -56,22 +56,25 @@ Returns the evaluation of
.Ar expr1
if it is neither an empty string nor zero;
otherwise, returns the evaluation of
-.Ar expr2 .
+.Ar expr2
+if it is not empty;
+otherwise, returns zero.
.It Ar expr1 Li & Ar expr2
Returns the evaluation of
.Ar expr1
if neither expression evaluates to an empty string or zero;
otherwise, returns zero.
.It Ar expr1 Li "{=, >, >=, <, <=, !=}" Ar expr2
-Returns the results of integer comparison if both arguments are integers;
-otherwise, returns the results of string comparison using the locale-specific
-collation sequence.
+Returns the result of the integer comparison if both arguments are integers;
+otherwise, returns the result of the string comparison
+using the locale-specific collation sequence.
The result of each comparison is 1 if the specified relation is true,
or 0 if the relation is false.
.It Ar expr1 Li "{+, -}" Ar expr2
-Returns the results of addition or subtraction of integer-valued arguments.
+Returns the result of addition or subtraction of integer-valued arguments.
.It Ar expr1 Li "{*, /, %}" Ar expr2
-Returns the results of multiplication, integer division, or remainder of integer-valued arguments.
+Returns the result of multiplication, integer division, or remainder
+of integer-valued arguments.
.It Ar expr1 Li \&: Ar expr2
The
.Dq \&:
@@ -79,7 +82,7 @@ operator matches
.Ar expr1
against
.Ar expr2 ,
-which must be a regular expression.
+the latter must be a regular expression.
The regular expression is anchored
to the beginning of the string with an implicit
.Dq ^ .
@@ -91,8 +94,8 @@ the string corresponding to
.Dq "\e1"
is returned;
otherwise the matching operator returns the number of characters matched.
-If the match fails and the pattern contains a regular expression subexpression
-the null string is returned;
+If the match fails and the pattern contains a regular expression subexpression,
+the empty string is returned;
otherwise 0.
.It "( " Ar expr No " )"
Parentheses are used for grouping in the usual manner.
@@ -208,7 +211,7 @@ expr "//$a" : '.*/\e(.*\e)'
According to
.St -p1003.2 ,
.Nm
-has to recognize special option
+has to recognize the special option
.Dq -- ,
treat it as a delimiter to mark the end of command
line options, and ignore it.
@@ -217,7 +220,7 @@ Some
implementations do not recognize it at all; others
might ignore it even in cases where doing so results in syntax
error.
-There should be same result for both following examples,
+There should be the same result for both following examples,
but it might not always be:
.Bl -enum -compact -offset indent
.It
