wc: expand help of '-L' (and a question)

[Assaf Gordon]

Hello,

Would you be willing to add the following patch, mentioning tab-expansion and 
multibyte counting of '-L'
in the "--help" screen, and the manual?
Currently this is mentioned only in one sentence at the end of a long 
paragraph, and is easily missed.
My wording could be improved, but I hope this will help prevent confusion with 
'wc -L' output.

Somewhat related:
I seem to get unexpected result with '-L' when forcing C locale.
Perhaps I'm doing something wrong, or there's more intricate details of '-L' ?

# This is a Unicode Character 'BLACK HEART SUIT' (U+2665)
$ printf "\xe2\x99\xa5\n"

# counting characters with UTF-8 locale is 1,
# Counting bytes is 3,
# longest line is 1 - as expected:
$ printf "\xe2\x99\xa5" | LC_ALL=en_US.UTF-8 wc -cmL
      1       3       1


# using C locale, characters=bytes=3,
# but longest line is 0 ?
$ printf "\xe2\x99\xa5" | LC_ALL=C wc -cmL
      3       3       0

This could be because of wc.c line 492, where "isprint" is called on each byte 
(e.g. isprint('\xe2') is false),
and so these characters are not counted at all?

thanks,
 - assaf

wc-longest-line-usage.patch
Description: Text Data