Raspian buster lite: grep fails with "Illegal instruction"

Question

Suddenly, grep has begun failing.

cat test.txt | grep hello

generates an "Illegal instruction" error. It makes no difference what's being piped in nor what PATTERN I use.

cat test.txt | less 
grep
grep -V
grep --help

all work fine

I've done a update and upgrade. How do I fix this?

MACE · Accepted Answer

SD card got corrupted.  Recreated and all works fine.  Not sure how to prevent it in the future.  Possibly related to the power.

One Answer