code: def CheckPrintf(filename, clean_lines, linenum, error):
    
    line = clean_lines.elided[linenum]
  
    # When snprintf is used, the second argument shouldn't be a literal.
    match = Search(r'snprintf\s*\(([^,]*),\s*([0-9]*)\s*,', line)
    if match and match.group(2) != '0':
      # If 2nd arg is zero, snprintf is used to calculate size.
      error(filename, linenum, 'runtime/printf', 3,
            'If you can, use sizeof(%s) instead of %s as the 2nd arg '
            'to snprintf.' % (match.group(1), match.group(2)))
  
    # Check if some verboten C functions are being used.
    if Search(r'\bsprintf\s*\(', line):
      error(filename, linenum, 'runtime/printf', 5,
            'Never use sprintf. Use snprintf instead.')
    match = Search(r'\b(strcpy|strcat)\s*\(', line)
    if match:
      error(filename, linenum, 'runtime/printf', 4,
            'Almost always, snprintf is better than %s' % match.group(1))
docs: Check for printf related issues.
  
    Args:
      filename: The name of the current file.
      clean_lines: A CleansedLines instance containing the file.
      linenum: The number of the line to check.
      error: The function to call with any errors found.