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Comment by l0b0 | Hacker News Reader

"One thing" has never been very well defined - basically every common Linux shell tool could be said to do more than one thing. GNU `grep` supports four different pattern styles (fixed strings, basic regex, extended regex and Perl regex), has lots of options for output formatting (counting, line numbers, whether to display file names, etc.) and has a bunch of rarely-used (but useful!) options for various corner cases, such as line buffering. Even GNU `cat`, the canonical "do one thing" tool, has several formatting options. If `grep` returned match objects rather than a semantically void binary stream it would be really easy to hand over formatting to another tool, but that just isn't how *nix tools work yet.

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> Even GNU `cat`, the canonical "do one thing" tool, has several formatting options.

Huh, TIL. It's just never occurred to me to even bother checking the help for cat.

  $ cat --help
  Usage: cat [OPTION]... [FILE]...
  Concatenate FILE(s) to standard output.
  
  With no FILE, or when FILE is -, read standard input.
  
    -A, --show-all           equivalent to -vET
    -b, --number-nonblank    number nonempty output lines, overrides -n
    -e                       equivalent to -vE
    -E, --show-ends          display $ at end of each line
    -n, --number             number all output lines
    -s, --squeeze-blank      suppress repeated empty output lines
    -t                       equivalent to -vT
    -T, --show-tabs          display TAB characters as ^I
    -u                       (ignored)
    -v, --show-nonprinting   use ^ and M- notation, except for LFD and TAB
        --help     display this help and exit
        --version  output version information and exit
  
  Examples:
    cat f - g  Output f's contents, then standard input, then g's contents.
    cat        Copy standard input to standard output.
  
  GNU coreutils online help: <http://www.gnu.org/software/coreutils/>
  Full documentation at: <http://www.gnu.org/software/coreutils/cat>
  or available locally via: info '(coreutils) cat invocation'

The thing I would like to see with grep is to have it optionally give me a 0 return code if it doesn't find anything.

I know why the authors chose to use a non-zero return code as the default, but when I'm using grep deep in a pipeline and doing my own checking of the results to see if nothing was found, I don't need grep bombing out the whole pipeline with a non-zero return code.

The alternative of being forced to use "(grep pattern||true)" instead of a plain "grep -q" is kinda painful.

I'm not in my computer now, but doesn't "grep -v" solves your issue? If I remember correctly, it inverts the query, so it would return 0 if there wasn't a match.

No, -v will return 0 unless every line matches:

  $ cat > foo
  here's
  some
  random
  text
  $ grep -v some foo; echo $?
  here's
  random
  text
  0
  $ grep -v bar foo; echo $?
  here's
  some
  random
  text
  0
  $ grep -vE "(here's|some|random|text)" foo; echo $?
  1

Would grep -c work for your use-case?

How about "awk /pattern/"?

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