How to check if a file exists in a shell script

Here is an alternative method using ls:

(ls x.txt && echo yes) || echo no

If you want to hide any output from ls so you only see yes or no, redirect stdout and stderr to /dev/null:

(ls x.txt >> /dev/null 2>&1 && echo yes) || echo no

You're missing a required space between the bracket and -e:

#!/bin/bash
if [ -e x.txt ]
then
    echo "ok"
else
    echo "nok"
fi

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