From: Jonathan Nieder <jrnieder@gmail.com>
Date: Sun, 9 Aug 2009 18:22:12 +0000 (-0500)
Subject: xzless: Support compressed standard input
X-Git-Tag: upstream/5.1.3~471
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=1d314b81aa5b0c4530638ffabd4e0edb52e5362c;p=platform%2Fupstream%2Fxz.git

xzless: Support compressed standard input

It can be somewhat confusing that

	less < some_file.txt

works fine, whereas

	xzless < some_file.txt.xz

does not.  Since version 429, ‘less’ allows a filter specified in
the LESSOPEN environment variable to preprocess its input even if
it comes from standard input, if $LESSOPEN begins with ‘|-’.  So
set $LESSOPEN to take advantage of this feature.

Check less’s version at runtime so xzless can continue to work
with older versions.
---

diff --git a/src/scripts/xzless.in b/src/scripts/xzless.in
index 6639943..a3da697 100644
--- a/src/scripts/xzless.in
+++ b/src/scripts/xzless.in
@@ -46,7 +46,13 @@ if test "${LESSMETACHARS+set}" != set; then
 	LESSMETACHARS="$space$tab$nl'"';*?"()<>[|&^`#\$%=~'
 fi
 
-LESSOPEN="|$xz -cdfq -- %s"
+if test "$(less -V | { read ver && echo ${ver#less }; })" -ge 429; then
+	# less 429 or later: LESSOPEN pipe will be used on
+	# standard input if $LESSOPEN begins with |-.
+	LESSOPEN="|-$xz -cdfq -- %s"
+else
+	LESSOPEN="|$xz -cdfq -- %s"
+fi
 export LESSMETACHARS LESSOPEN
 
 exec less "$@"