[PATCH] fcntl F_SETFL and read-only IS_APPEND files
There is code in setfl() which attempts to preserve the O_APPEND flag on
IS_APPEND files... however IS_APPEND files could also be opened O_RDONLY
and in that case setfl() should not require O_APPEND...
coreutils 5.93 tail -f attempts to set O_NONBLOCK even on regular files...
unfortunately if you try this on an append-only log file the result is
this:
fcntl64(3, F_GETFL) = 0x8000 (flags O_RDONLY|O_LARGEFILE)
fcntl64(3, F_SETFL, O_RDONLY|O_NONBLOCK|O_LARGEFILE) = -1 EPERM (Operation not permitted)
I offer up the patch below as one way of fixing the problem... i've tested
it fixes the problem with tail -f but haven't really tested beyond that.
(I also reported the coreutils bug upstream... it shouldn't fail imho...
<https://savannah.gnu.org/bugs/index.php?func=detailitem&item_id=15473>)
Signed-off-by: dean gaudet <dean@arctic.org>
Cc: Al Viro <viro@ftp.linux.org.uk>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
1 file changed