bash - If statement to display error if data is not present in a file -

  echo "Please enter a forum"; Forum; if [ ! $ Foreman]; Then echo "$ Forename not found"; Else grep -n "Forename: $ Forename" $ ​​filename | type;  

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I am trying to use the above code to check that the user entering the string in the file exists, the file name is < Code> Address Book Txt which I assigned to the variable filename .

Can someone advise me whether this will work or recommend a better way of checking the file. You can print the contents of the file by using the cat for example:

You can now check that the string content is empty:

  if [- N "$ Content"]; Then you can use the  grep   

Code> content = $ (grep "$ pattern" "$ filename")

and if it will be the same