Bug in grep with -i

[Jon Tulk]

The -i flag in combination with case-sensitive symbols in a regular 
expression gives incorrect results.  I found this bug with the "\W"
symbol but have not tested any others. 

Example: 

 grep -i "\WIL\W" 

Expected behaviour is to find all lines containing "IL" (caseblind) as
a word.  Actual result is to find all lines containing "IL" (caseblind)
only where embedded in a word. 

From this result, I imply that the -i flag is causing the entire pattern
to be lower-cased prior to intrepretation of the "\W" symbol.  The same
result is achieved by the command: 

 grep -i "\wil\w" 


The examples below were run using the attached data file. 

-bash-2.05b$ egrep "\WIL\W" sample
14 60970 IL WATSEKA
14 62868 IL NOBLE 

-bash-2.05b$ egrep -i "\WIL\W" sample
4 72339 AR GILMORE
43 37237 TN NASHVILLE
44 75562 TX KILDARE
47 20142 VA ROUND HILL
49 24842 WV HEMPHILL 

-bash-2.05b$ egrep -i "\wil\w" sample
4 72339 AR GILMORE
43 37237 TN NASHVILLE
44 75562 TX KILDARE
47 20142 VA ROUND HILL
49 24842 WV HEMPHILL 

-bash-2.05b$ grep -V
grep (GNU grep) 2.5.1 

Copyright 1988, 1992-1999, 2000, 2001 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 


This is running on Red Hat Advanced Server 3.0 


I hope I'm not wasting your time on a duplicate.  I couldn't find this one 
in your archives. 

Regards,
Jon Tulk

sample
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