Matching all words with a hashtag(#) in shell script

Question

Can anyone give me a quick way to extract all hashtags in a given sentence using shell scripts.

For example: 'This is a #test that will #allow me to #remove stuff' would return #test #allow #remove

Answer 1

You may want to try egrep -o '#[^ ]+'. The output should look like:

#test
#allow
#remove

Answer 2

Just to provide an alternative with awk:

awk '{for (i=1; i<=NF; i++) if ($i ~ /^#/) print $i}'

And here is pure BASH way of extracting these mathes:

x=$str # your original string
while :; do
   if [[ $x =~ (\#[a-z]+)(.*)$ ]]; then
      echo "${BASH_REMATCH[1]}"
      x="${BASH_REMATCH[2]}"
   else
      break
   fi
done