I wonder what is the reason behind the naming convention? What is the downside of simply writing to any present fifo file ?
It could work like you're suggesting. But : - checking the type of a file is an additional fstat() system call - there may be reasons in the future to store other files in the fifodir that do not receive the event - it is nice to detect stale fifos, if any, and delete them as soon as you can (#L39), and you don't want to delete unrelated files - but most importantly: creating a fifo in a fifodir that allows you to receive events without a race condition, which is the whole point of the ftrig library, is slightly more complex to do safely than just "mkfifo event/foobar", and I don't want people to think that this is the API. No, the API is ftrigr_subscribe(), and everything under it is implementation details. Restricting the naming is a way of ensuring (as much as possible) that the fifos were indeed created by the appropriate programs. Don't create fifos willy-nilly in a fifodir, and since you found the naming convention, don't use it to work around the check to create your fifos outside of ftrigr_subscribe(). If you do, it will work, until the time when it doesn't, and it will be a complete PITA to debug. -- Laurent
