[pacman-dev] [PATCH 1/1] alpm: use flock() for db lock

[Andrew Gregory]

On 06/06/17 at 11:26pm, Christian Hesse wrote:
> From: Christian Hesse <mail at eworm.de>
> 
> We used to check for file existens, but that suffers from stale lock
> files caused by unexpected events like crash, shutdown, etc.
> 
> Instead use flock() to lock the file. It does not matter whether or
> not the file exists but whether an exclusive lock can be obtained.
> 
> Also remove the hint about removing the file from pacman.
> 
> Signed-off-by: Christian Hesse <mail at eworm.de>
> ---
>  lib/libalpm/handle.c | 17 +++++++++++++++--
>  src/pacman/util.c    |  5 -----
>  2 files changed, 15 insertions(+), 7 deletions(-)

Refusing to run when a lock file is leftover from a previous
invocation is intentional.  It serves as an indicator that the user
needs to verify the integrity of their system.  Also, see
https://lists.archlinux.org/pipermail/pacman-dev/2013-August/017733.html
for previous discussion regarding flock().

apg