Bash has native redirection that can check for open ports

host=192.168.1.99
if (echo > "/dev/tcp/${host}/22") >/dev/null 2>&1; then
  echo 'port is open'
else
  echo 'port is closed'
fi

or you can use nc(1):

host=192.168.1.99
if timeout 3 nc -z "$host" 22 2>/dev/null; then
  echo 'port is open'
else
  echo 'port is closed'
fi

You can also use telnet programmatically by piping it to something like grep:

host=192.168.1.99
if telnet "$host" 22 2>&1 | grep -q "Connected"
  echo 'port is open'
else
  echo 'port is closed'
fi

Bash has native redirection that can check for open ports

host=192.168.1.99
if (echo > "/dev/tcp/${host}/22") >/dev/null 2>&1; then
  echo 'port is open'
else
  echo 'port is closed'
fi

or you can use nc(1):

host=192.168.1.99
if timeout 3 nc -z "$host" 22 2>/dev/null; then
  echo 'port is open'
else
  echo 'port is closed'
fi

You can also use telnet programmatically by piping it to something like grep:

host=192.168.1.99
if telnet "$host" 22 2>&1 | grep -q "Connected"; then
  echo 'port is open'
else
  echo 'port is closed'
fi