I have this set of example here to test if the user has keyed in any data after he presses enter.echo -n Type a digit or a letter > read characterblank=if  [ $character != $blank]; then        echo You typed somethingelse    echo Enter somethingfiThe code above should be testing if the variable contains anything, but I can't seem to get it to work, any help ? Much appreciated.
How do i create a function to test if the input contains any character?
shell;string;test
You can simply use [ $character ] to test if string is nonzero, what is equivalent of longer form [ -n $character ]. Alternatively [ -z $character ] to test if string is zero.However many times in interactive scripts what is really needed is to set some default value in the variable which user can override. If this is your intention then you can avoid test and use parameter expansion:read characterecho character is set to ${character:-default}