bin/172862: sed improperly deals with escape chars

[Garrett Cooper]

>Number:         172862
>Category:       bin
>Synopsis:       sed improperly deals with escape chars
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Thu Oct 18 21:10:00 UTC 2012
>Closed-Date:
>Last-Modified:
>Originator:     Garrett Cooper
>Release:        9.1-STABLE
>Organization:
EMC Isilon
>Environment:
FreeBSD bayonetta.local 9.1-PRERELEASE FreeBSD 9.1-PRERELEASE #0 r240836M: Sat Sep 22 12:30:11 PDT 2012     gcooper at bayonetta.local:/usr/obj/store/freebsd/stable/9/sys/BAYONETTA  amd64
>Description:
sed doesn't appear to be doing the right thing with escape chars (in this case '\t'); it's not properly reinterpreting '\t' as \011, but is instead interpreting it was 't':

$ echo "foot " | sed -e 's/[\\t ]*$//' | hexdump -C
00000000  66 6f 6f 0a                                       |foo.|
00000004
$ echo "foot " | sed -E -e 's/[\\t ]*$//' | hexdump -C
00000000  66 6f 6f 0a                                       |foo.|
00000004

GNU sed does do the right thing with escape chars (verified on Fedora 17):

# cat /etc/redhat-release
Fedora release 17 (Beefy Miracle)
# echo foot | sed -e 's/[\t ]*$//' | hexdump -C
00000000  66 6f 6f 74 0a                                    |foot.|
00000005
# echo "foot " | sed -e 's/[\t ]*$//' | hexdump -C
00000000  66 6f 6f 74 0a                                    |foot.|
00000005
>How-To-Repeat:
echo foot | sed -e 's/[\t ]*$//'
>Fix:


>Release-Note:
>Audit-Trail:
>Unformatted: