Aren/NetBSD
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Explicitly quote | and : meant as separate operator. Kill trailing

Browse Source 
whitespace. Don't use \Z' with obscure character entity. Reorder sections
to canonical order.
This commit is contained in:
joerg 2010-05-24 00:29:30 +00:00
parent 0ae4c88a36
commit 52bf796fd6
1 changed files with 37 additions and 37 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

74
bin/expr/expr.1
View File

@ -1,4 +1,4 @@
.\" $NetBSD: expr.1,v 1.29 2008/04/30 13:10:46 martin Exp $
.\" $NetBSD: expr.1,v 1.30 2010/05/24 00:29:30 joerg Exp $
.\"
.\" Copyright (c) 2000,2003 The NetBSD Foundation, Inc.
.\" All rights reserved.
@ -51,7 +51,7 @@ Characters special to the command interpreter must be escaped.
Operators are listed below in order of increasing precedence.
Operators with equal precedence are grouped within { } symbols.
.Bl -tag -width indent
.It Ar expr1 Li | Ar expr2
.It Ar expr1 Li \&| Ar expr2
Returns the evaluation of
.Ar expr1
if it is neither an empty string nor zero;
@ -72,7 +72,7 @@ or 0 if the relation is false.
Returns the results 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.
.It Ar expr1 Li : Ar expr2
.It Ar expr1 Li \&: Ar expr2
The
.Dq \&:
operator matches
@ -100,7 +100,7 @@ Parentheses are used for grouping in the usual manner.
.Pp
Additionally, the following keywords are recognized:
.Bl -tag -width indent
.It length Ar expr
.It length Ar expr
Returns the length of the specified string in bytes.
.El
.Pp
@ -126,7 +126,7 @@ compare operators
.It
.Dq \*[Am]
.It
.Dq \Z'\*[tty-rn]'|
.Dq \&|
.El
.Sh EXIT STATUS
The
@ -159,38 +159,6 @@ in variable a.
The following example returns the number of characters in variable a.
.Dl expr $a Li : '.*'
.El
.Sh STANDARDS
The
.Nm
utility conforms to
.St -p1003.2 .
The
.Ar length
keyword is an extension for compatibility with GNU
.Nm .
.Sh AUTHORS
Original implementation was written by
.An J.T. Conklin
.Aq jtc@NetBSD.org .
It was rewritten for
.Nx 1.6
by
.An Jaromir Dolecek
.Aq jdolecek@NetBSD.org .
.Sh NOTES
The empty string
.Dq
cannot be matched with the intuitive:
.Bd -literal -offset indent
expr '' : '$'
.Ed
.Pp
The reason is that the returned number of matched characters (zero)
is indistinguishable from a failed match, so this returns failure.
To match the empty string, use something like:
.Bd -literal -offset indent
expr x'' : 'x$'
.Ed
.Sh COMPATIBILITY
This implementation of
.Nm
@ -249,3 +217,35 @@ Although
handles both cases correctly, you should not depend on this behavior
for portability reasons and avoid passing bare '--' as first
argument.
.Sh STANDARDS
The
.Nm
utility conforms to
.St -p1003.2 .
The
.Ar length
keyword is an extension for compatibility with GNU
.Nm .
.Sh AUTHORS
Original implementation was written by
.An J.T. Conklin
.Aq jtc@NetBSD.org .
It was rewritten for
.Nx 1.6
by
.An Jaromir Dolecek
.Aq jdolecek@NetBSD.org .
.Sh NOTES
The empty string
.Do Dc
cannot be matched with the intuitive:
.Bd -literal -offset indent
expr '' : '$'
.Ed
.Pp
The reason is that the returned number of matched characters (zero)
is indistinguishable from a failed match, so this returns failure.
To match the empty string, use something like:
.Bd -literal -offset indent
expr x'' : 'x$'
.Ed