backfire(4) send a signal from driver to user


The backfire driver reads a numerical string that is sent to the /dev/backfire device and sends the corresponding signal to the calling user program. Reading from /dev/backfire returns the time of the day when the most recent sent request was serviced or 0, if a sent request was not yet received. The time of the day is displayed in seconds since 1970-01-01 00:00:00 UTC followed by the fraction of the second in microseconds separated by a comma.


The backfire driver is normally used in combination with the program sendme to benchmark the performance of the kernel's signal sending capabilities.


head -1 /dev/backfire
trap "echo Got signal 7" 7
echo 7 >/dev/backfire
Got signal 7
head -1 /dev/backfire


Carsten Emde <[email protected]>