2

My issues is that I want to read a character from the stdin and compare it with a string value. If that character exists then I want to display a message. Eg, saving % into the variable $a:

$ read a
%
$echo $a
%

There is variable defined say v='~`!@#$%^&*()_-+=:;{[}]|\/<>,."' all possible special character including single tick '

I need to check if the character input exists in the string value. How can I do this.

2
case $v in
  *"$a"*) printf '<%s> is in <%s>\n' "$a" "$v"
esac
1

Here you go:

#!/bin/bash
v='~`!@#$%^&*()_-+=:;{[}]|/<>,."'
echo type any character and press enter
IFS= read -r a
[[ $v =~ "$a" ]] && echo match || echo not
  • Janos, I didn't know how to run this from the script: [[ $v =~ $a ]] && echo match || echo not – Nirmal Arri Jan 16 '14 at 22:31
  • @NirmalArri save the script for example in script.sh, and run it with bash script.sh – janos Jan 16 '14 at 22:52
-1

Try this

cat | egrep -e '[~`!@#$%^&*()_-+=:;{[}]|/<>,."]'
  • What are you cating here? Did you mean something like echo "$a" | grep -E ["$v"]? – terdon Jan 16 '14 at 23:22
  • 1
    No, not quite: the first ] marks the end of the set. – Gilles 'SO- stop being evil' Jan 16 '14 at 23:48
  • @Giles You're correct hadn't noticed that! – X Tian Jan 17 '14 at 1:32
  • @terdon I just typed a couple of test lines straight into cat, but agree your use of variables closer to question. – X Tian Jan 17 '14 at 1:32

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