expect:tldr:90da3

The given command is using the expect utility with a one-line script provided as an argument through the -c option.

Here's a breakdown of the command:

• expect is a program used to automate interactive applications by scripting their behavior.
• -c is an option that allows specifying the commands directly as an argument, rather than from a separate script file.
• ${commands} is a placeholder for the actual commands that need to be executed.

In practice, you would replace ${commands} with the actual code or script you want expect to execute. For example, if you want to automate a series of interactions with an application, you would place those interactions as a series of commands inside ${commands}.

To give a clearer understanding, here's an example of how you could use the expect command with the -c option:

expect -c "
  spawn ssh user@hostname
  expect \"password:\"
  send \"MyPassword\r\"
  expect \"\$ \"
  send \"ls\r\"
  expect \"\$ \"
  send \"exit\r\"
  expect eof
"

In the above example, the expect command connects to a remote host using SSH, sends the password, executes the ls command, exits the SSH session, and expects the end of the connection. This particular script is given directly to expect using the -c option.