#!/usr/bin/bash
echo -e "Enter name of th file:\c"
read file_name
if [ -f $file_name ]
then
if [ -w $file_name ]
then
echo "Type some test data. To quit press ctrl+d."
cat&gt;&gt; $file_name
else
echo "The file do not have write permission"
fi
else
echo "$file_name not exists"
fi

#!/usr/bin/bash

echo -e "Enter name of th file:\\c"

read file\_name

if \[ -f $file\_name \]

then

if \[ -w $file\_name \]

then

echo "Type some test data. To quit press ctrl+d."

cat&gt;&gt; $file\_name

else

echo "The file do not have write permission"

fi

else

echo "$file\_name not exists"

fi

Shell Scripting - How to append output to the end of text file