Help needed to add text to the end of a string using the "sed" command in Terminal
So here is my question… is there a similar character I can use, like
  the "^" character, that would allow me to use the sed command to add
  text to the end of each line?


Yes, it is: $

That said, looking at what is is going on, let me offer you a different over all solution where you do not need to first:

cat curlFTP.txt | cut -c 52- &gt; curlFTP2.txt


You can process the curlFTP.txt file directly and completely with sed:

sed -E -e 's|^.*[A-Za-z]{3}[ ][0-9]{2}[ ][0-9]{4}[ ]|curl ftp://1.1.1.1/Disk 1 Movies/Movies 1/|' -e 's|$|/|' curlFTP.txt &gt; newfile.txt


You could even eliminate &gt; newfile.txtby using the -i option of the sed command:


  −i extension Edit files in-place, saving backups with the specified
  extension. If a zero-length extension is given, no backup will be
  saved. It is not recommended to give a zero-length extension when
  in-place editing files, as you risk corruption or partial content in
  situations where disk space is exhausted, etc.


sed -i'.bak' -E -e 's|^.*[A-Za-z]{3}[ ][0-9]{2}[ ][0-9]{4}[ ]|curl ftp://1.1.1.1/Disk 1 Movies/Movies 1/|' -e 's|$|/|' curlFTP.txt




Using https://regex101.com to explain the regex used in the sed command:



Which matches e.g.:

drwxr-xr-x 1 nobody root 4096 Aug 02 2014