How can I have grep not print out 'No such file or directory' errors?

user_265629 0
Viewed 196908

I'm grepping through a large pile of code managed by git, and whenever I do a grep, I see piles and piles of messages of the form: 

> grep pattern * -R -n
whatever/.git/svn: No such file or directory

Is there any way I can make those lines go away?

grep
10 Answers

I redirect stderr to stdout and then use grep's invert-match (-v) to exclude the warning/error string that I want to hide:

grep -r <pattern> * 2>&1 | grep -v "No such file or directory"
user_133263480

I was getting lots of these errors running "M-x rgrep" from Emacs on Windows with /Git/usr/bin in my PATH. Apparently in that case, M-x rgrep uses "NUL" (the Windows null device) rather than "/dev/null". I fixed the issue by adding this to .emacs:

;; Prevent issues with the Windows null device (NUL)
;; when using cygwin find with rgrep.
(defadvice grep-compute-defaults (around grep-compute-defaults-advice-null-device)
  "Use cygwin's /dev/null as the null-device."
  (let ((null-device "/dev/null"))
    ad-do-it))
(ad-activate 'grep-compute-defaults)
user_7830370

One easy way to make grep return zero status all the time is to use || true

 → echo "Hello" | grep "This won't be found" || true

 → echo $?
   0

As you can see the output value here is 0 (Success)

user_110266060
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