Package: grep
Version: 3.1-2


I am trying to use grep -w to match a word, but it seems that grep ignores
the -w switch and returns all occurencies.

Test case:
$ cat file1
one two three

$ grep -w 'two' file1 #or grep -Ew 'two'
Result: all four lines of file1 are returned.

According  to man grep:
-w, --word-regexp
              Select only those lines containing matches that form whole
words.  The test is  that  the  matching  substring  must either  be  at
the  beginning  of the line, or preceded by a non-word constituent
character.  Similarly, it must be either at the end of the line or followed
by a non-word  constituent  character. Word-constituent  characters
are letters,
digits, and the underscore.  This option has no effect if -x is also

Since dash '-' does not belong to word-constituent characters i was
expecting only first line to be matched : one two three

Just for the record , even options \<two\>, or \btwo\b will also return all
four lines.

Easy workaround for the job would be to use
grep ' two ' or grep -E '\stwo\s'

But this bug report is focused on the failure of -w flag


George Vasiliou

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