Synnefo » snf-ganeti » ganeti-local

def TailFile(fname, lines=20):

  """Return the last lines from a file.

  @note: this function will only read and parse the last 4KB of

      the file; if the lines are very long, it could be that less

      than the requested number of lines are returned

  @param fname: the file name

  @type lines: int

  @param lines: the (maximum) number of lines to return

  """

  fd = open(fname, "r")

  try:

    fd.seek(0, 2)

    pos = fd.tell()

    pos = max(0, pos-4096)

    fd.seek(pos, 0)

    raw_data = fd.read()

  finally:

    fd.close()

  rows = raw_data.splitlines()

  return rows[-lines:]