Displaying only data matching a pattern?

[Ben Scott]

On Mon, Feb 2, 2009 at 11:58 AM, Michael ODonnell
<michael.odonnell at comcast.net> wrote:
>>  sed s/.*:\([[:xdigit:]]*\)\\.*/\1/
>
> That looks good to me, though I assume he meant to show that
> expression in single quotes.

  Nope.  The Windows NT shell (CMD.EXE) has different meta-characters
from Bourne and company.  In particular, asterisk (*), backslash (\),
and square brackets ([]) are *not* shell meta-characters.

> Also, I can't remember if those character class notations count
> as Extended Regular Expressions but ...

  The sed from unxutils apparently only supports Basic Regular
Expressions.  At least, it doesn't recognize the + one-or-more
modifier.  It does recognize the named character classes, though.  I
did run my command line on a whole one test case.  ;-)

  According to a random "sed" man page I found on the web, the named
character classes are part of POSIX BREs.

-- Ben