How to get the IP address from $SSH_CLIENT

Question

$SSH_CLIENT has IP address with some port info, and echo $SSH_CLIENT gives me '10.0.40.177 52335 22', and Running

if [ -n "$SSH_CONNECTION" ] ; then for i in $SSH_CLIENT do echo $i done fi

gives me

• 10.0.40.177
• 52335
• 22

And I see the first element is the IP address.

Q : How can I get the first element of $SSH_CLIENT? ${SSH_CLIENT[0]} doesn't work.

Answer 1

sshvars=($SSH_CLIENT)
echo "${sshvars[0]}"

or:

echo "${SSH_CLIENT%% *}"

Answer 2

For strings, as is the case here, the <<< operator may be used:

$ read ipaddress outport inport <<< $SSH_CLIENT

See e.g: Linux Bash: Multiple variable assignment. Don't do this with binary input though: Is there a binary safe <<< in bash?