topic Re: busy file in Operating System - HP-UX

busy file

Prashanth Waugh — Thu, 30 Aug 2007 00:58:09 GMT

hi,
I AM trying to copy the file to another destination it is showing busy.so can i
use #fuser -ku
Thanks

Re: busy file

Dennis Handly — Thu, 30 Aug 2007 01:53:43 GMT

I assume the target of the copy is busy and it is an executable or shlib?

There is no need to use a fuser/lsof hammer. Just use ln -f and teach that guy a lesson: ;-)
cp path/file file.new
ln file file.old
ln -f file.new file
rm file.new

Re: busy file

Wim Rombauts — Thu, 30 Aug 2007 01:59:35 GMT

I guess that even a

"mv targetfile targetfile.old"

followed by a

"cp sourcefile targetfile"

should work. The targetfile is opened by it's inode, and by moving the file, the inode remains untouched, just the name is changed. The current user will keep using the old file until he closes and reopens it. New users wil use the new file.

Re: busy file

whiteknight — Thu, 30 Aug 2007 02:51:34 GMT

Hi,

A busy file on UNIX is one which cannot be unlinked (unlink(2)), not necessarily any open file as reported by fuser(1M). Busy and open being synonymous is the case with Windows.

When a file is overwritten, its inode (the pointer to the data, named by the file's name) is unlinked from the data. If a process has the data open, then that data will continue to use disk space until the process exits. But since the inode could be unlinked from the old data, the file name is free to be used for a new inode pointing to the restored data.

Had the unlink(2) failed, common with shared library files, then the inode would be renamed to # from . Then the old filename would be free to use with a new inode pointing to the restored data, while the old inode, now named #, still points to the old data.

WK

Re: busy file

Dennis Handly — Thu, 30 Aug 2007 03:27:45 GMT

>Wim: I guess that even a "mv" followed by a "cp" should work.

This won't work in all cases. I.e. replacing dld.
Only ln(1) works, so don't settle for cheap imitations. ;-)

>WK: Had the unlink(2) failed, common with shared library files, then the inode would be renamed to # from .

This "#" convention is a manual process, which must be programmed into the script.