Bug #7303

Logger fails on log rotation in Windows (log shifting failed. Permission denied)

Added by pink-ink (Herman Munster) over 4 years ago. Updated over 4 years ago.

Target version:
ruby -v:
ruby 1.9.3p0 (2011-10-30) [i386-mingw32]


I have the problem that the logger fails in rotating the log file (daily) with Ruby 1.9.3 in Windows 7.

The cause is, that the log file is open and shall be renamed.
This results in an error "log shifting failed. Permission denied".

Log rotating will work, if the log file is copied to the age_file and then the logfile is cleaned by using logdev.truncate(0).

My changes to logger.rb are (remove 3 lines, add 2 lines):

def shift_log_period(period_end)
  postfix = period_end.strftime("%Y%m%d")# YYYYMMDD
  age_file = "#{@filename}.#{postfix}"
  if FileTest.exist?(age_file)
    # try to avoid filename crash caused by Timestamp change.
    idx = 0
    # .99 can be overridden; avoid too much file search with 'loop do'
    while idx < 100
      idx += 1
      age_file = "#{@filename}.#{postfix}.#{idx}"
      break unless FileTest.exist?(age_file)
  • @dev.close rescue nil
  • File.rename("#{@filename}", age_file)
  • @dev = create_logfile(@filename)
  • FileUtils.cp(@filename, age_file)
  • reset_logfile(@dev) # see below for this new method return true

I've added a new method to clean the open logfile and add a log header:
def reset_logfile(logdev)
logdev.truncate( 0 )
logdev.sync = true

The change above (copy/clean instead of rename) should also be
applied to the method "shift_log_age", same problem here.

I don't know how to bring this code into standard ruby sources.
Please somebody change the code, so the bug will be fixed.

(I found this bug also described in the old RubyForge archive:


#1 [ruby-core:49037] Updated by pink-ink (Herman Munster) over 4 years ago

Addition to my previous post:
require 'fileutils' is needed at the beginning of logger.rb, if using FileUtils.cp().

#2 [ruby-core:51043] Updated by usa (Usaku NAKAMURA) over 4 years ago

  • Status changed from Open to Assigned

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