From d26fd835e7dee88b385c24b887dce1f25737a7b6 Mon Sep 17 00:00:00 2001 From: jilles Date: Fri, 10 Sep 2010 14:00:27 +0000 Subject: [PATCH] test(1): Clarify grammar ambiguity and -a/-o vs shell &&/||. --- bin/test/test.1 | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/bin/test/test.1 b/bin/test/test.1 index 726542da4f17..cbeff94bb6a3 100644 --- a/bin/test/test.1 +++ b/bin/test/test.1 @@ -32,7 +32,7 @@ .\" @(#)test.1 8.1 (Berkeley) 5/31/93 .\" $FreeBSD$ .\" -.Dd July 31, 2006 +.Dd September 10, 2010 .Dt TEST 1 .Os .Sh NAME @@ -310,6 +310,14 @@ are evaluated consistently according to the rules specified in the standards document. All other cases are subject to the ambiguity in the command semantics. +.Pp +In particular, only expressions containing +.Fl a , +.Fl o , +.Cm \&( +or +.Cm \&) +can be ambiguous. .Sh EXIT STATUS The .Nm @@ -338,12 +346,11 @@ specification. Both sides are always evaluated in .Fl a and -.Fl o , -unlike in the logical operators of -.Xr sh 1 . +.Fl o . For instance, the writable status of .Pa file will be tested by the following command even though the former expression indicated false, which results in a gratuitous access to the file system: -.Pp .Dl "[ -z abc -a -w file ]" +To avoid this, write +.Dl "[ -z abc ] && [ -w file ]"