How to echo shell commands as they are executed?

 

You can echo shell commands as they are executed in a script by using the -x option with the #!/bin/bash shebang at the beginning of your script. This option is often called "shell tracing." It displays each command, along with its arguments and the results of variable expansions, as it is executed. Here's an example:

Create a shell script (e.g., myscript.sh) with the following content:

bash

#!/bin/bash -x

echo "This is a shell script."

# Some commands
foo="Hello"
bar="World"

echo "$foo, $bar!"

In this script:

1. #!/bin/bash -x specifies that the script should be interpreted by the Bash shell with the -x option, enabling the shell tracing feature.

2. The script contains some simple commands and variable assignments.

3. When you run the script, you will see the output of each command along with their results, including variable expansions:

   bash

3. + echo 'This is a shell script.'
   This is a shell script.
   + foo=Hello
   + bar=World
   + echo 'Hello, World!'
   Hello, World!
   

The + symbol at the beginning of each line indicates the trace output. This feature can be helpful for debugging and understanding the execution flow of your shell script. To disable tracing, you can remove the -x option or simply run the script without it.