Hi, there is a bug on file locking (via fcntl) on
linux kernel 2.4.19 when locking files in a NFS
volume.
Try to mount a remote NFS server on a directory in a
machine running Linux 2.4.19 as follows:
mount -o nfsvers=3,intr <remote NFS server path> /mnt
Then run the attached program which demonstrates the
bug:
lockbug /mnt/xx
and it keeps showing the error
lock failed with error: No locks available
The file has not been locked so there must be locks
available. The error message is wrong.
Trying this on a file in a local drive does not show
the error.
The attached program basically forks a child and in
the child it tries to lock a file descriptor that was
opened in the parent.
Thanks for any help on working around this bug.
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