tail is reading already rotated file.

[최종우]

I am using GNU coreutils 8.4 with flume 1.4.0, log4j 1.2.17.

I've found a problem that sometimes tail run by flume is reading a file has been renamed by log4j.

flume executed tail with following parameters:
tail -F logfilename

Fist flume had run the command, I checked file descriptors opened by tail process:
ls -l /proc/pid/fd

0 -> pipe:[185694192] // Sorry, I am not sure that the numbers are correct.
1 -> pipe:[185694193]
2 -> pipe:[185694194]
4 -> inotify
5 -> logfilename

After time passed, log4j had rotated the log file, I rechecked file descriptos:
ls -l /proc/pid/fd

0 -> pipe:[185694192] // Sorry, I am not sure that the numbers are correct.
1 -> pipe:[185694193]
2 -> pipe:[185694194]
4 -> inotify
5 -> logfilename.1


tail has been being executed with a parameter '-F', but didn't follow by name.
This problem doesn't happen always. I don't know why this problem happened.