In other post I will show you how

Status

Check this post to learn about exit status :

https://jrichardsz.github.io/linux/exit-status-of-a-command

sdout stderr

Check this post to learn about exit status :

https://jrichardsz.github.io/java/stdout-stderr-in-devops

sudo

Now is the turn of sudo. Almost all tools needs this permission. So I needed detect if sudo are allowed. This line do that:

sudo -nv

If this line is executed from a root user, does not return anything, but if a user with no privileges , return this :

sudo: a password is required

And thanks to Duke god, status is a nonzero value, so …

sudo_detect() {
  prompt=$(sudo -nv > /dev/null 2>&1)
  status=$?
  echo $status
}

if [ "$(sudo_detect)" -eq "0" ]; then
  echo "sudo is allowed"
else
  echo "sudo is not allowed. Bye!"

Check this post

https://jrichardsz.github.io/java/stdout-stderr-in-devops

to learn about > /dev/null 2>&1 :

Other example : Detect Java

java_detect() {
  java_version=$(java -version > /dev/null 2>&1)
  status=$?
  echo $status
}

if [ "$(java_detect)" -eq "0" ]; then
  echo "java is installed"
else
  echo "java is not installed"

That’s it for today.

Until the next,
JRichardsz