grep: 'binary files' where matches are text

[eavis]

It's useful that GNU grep, by default, avoids printing binary garbage to 
the terminal by skipping over files that it considers 'binary'.  But 
surely the important issue is not whether the file contains binary data, 
but whether the matches found are printable.

I would like to suggest a new option, although I do not know what it 
should be called:

  --foo
    Search all files for matches, even binary files, but if a match is 
found that contains binary data just print a message 'match containing 
binary data in file X' instead of printing that match.

This is subtly different from the current behaviour of grep, which will 
summarize the whole file with 'matches found' even if most of those 
matches could be safely printed.  In fact, I would even venture to say 
that this behaviour should be the default, since it prints as many matches 
as possible without generating unprintable characters.

Perhaps this option could fit into the existing --binary-files choices: 
--binary-files=print_text_matches or some such.  But (opinion) I don't 
think the --binary-files option is a particularly neat or self-explanatory 
way of presenting these choices.  As I said above, what really matters is 
whether the _matches_ are binary, not the input files.  Perhaps a single 
Boolean option for 'print binary matches' would cover most needs.

BTW, what prompted me to suggest this was:

% set | grep FRED
Binary file (standard input) matches
% set | grep --text FRED
FRED=fred

There was no need for grep to be so reticent, just because there were a 
few binary characters in the output of 'set' amid a much larger amount of 
ASCII text.

-- 
Ed Avis <address@hidden>