On 02/11/2013 03:29 PM, Pádraig Brady wrote:
On 02/11/2013 02:56 AM, Tom Warzeka wrote:
Hello! I sometimes use 'cat -E' as a quick check for lines with trailing
white space. I understand that '$' was chosen as the end-of-line
character due to its usage in regular expressions. However, I like to
use a more conspicuous character, such as '@'. So, I thought, how about
letting the user specify the end-of-line character? While doable with
'sed', it was quite easy to add an option to accomplish this. My
proposed new syntax is:
cat -E -c @ ...
or
cat --show-ends --end-char=@ ...
It is minimally intrusive and does not affect backward compatibility:
when one of the new options is not specified, the end-of-line character
is still '$'. Alternatively, use of one of these options could
automatically turn-on displaying an end-of-line character
(just add "show_ends = true;" within the new case).
Here's my patch submitted for your perusal. It is applied to
coreutils-8.20, the current latest stable release. If you decide to
include it, feel free to make any changes you see fit. Thanks!
-- Tom
Why is @ (or any char) better than $ ?
If you wanted to highlight stuff you'd be better with grep or sed:
cat -E < the/file | GREP_COLOR='30;41' grep --color '[[:space:]]*\$$'
I don't think there is enough benefit for including this change.
BTW if you're only interested in looking at trailing whitespace,
then the trailing $, and thus `cat` is redundant anyway:
# Show all lines with trailing whitespace highlighted
$ GREP_COLOR='41' grep --color '[[:blank:]]*$'
# Show lines with trailing whitespace highlighted
$ GREP_COLOR='41' grep --color '[[:blank:]]\+$'
cheers,
Pádraig.