echo command does one simple job: it prints to the output the argument passed to it.
hello to the terminal.
We can append the output to a file:
echo "hello" >> output.txt
We can interpolate environment variables:
echo "The path variable is $PATH"
Beware that special characters need to be escaped with a backslash
$ for example:
This is just the start. We can do some nice things when it comes to interacting with the shell features.
We can echo the files in the current folder:
We can echo the files in the current folder that start with the letter
Any valid Bash (or any shell you are using) command and feature can be used here.
You can print your home folder path:
You can also execute commands, and print the result to the standard output (or to file, as you saw):
echo $(ls -al)
Note that whitespace is not preserved by default. You need to wrap the command in double quotes to do so:
You can generate a list of strings, for example ranges:
echocommand works on Linux, macOS, WSL, and anywhere you have a UNIX environment