I have never been much of an AWK fan. In fact I have almost never used it. However, today it did serve me well:

• The problem:
  •       Add a semi colon (;) at the end of each line of a text file
• The solution:
  • cat file.txt | awk '{print $0 ";"}'
• Solution explained:
  • awk executes the script repeatedly for each line of the input file
  • $0 represents each complete line of the file
  • The matching pattern is empty, so the rule executes always, for each line. Thus the print statement adds the required semicolon