real time

POSIX real-time signals in Linux

1.0 Signals

Signals are notifications delivered asynchronously to a process by the kernel. Signals are grouped in two categories. First, there are standard signals, which have been there since the early days of Unix. Second, there are POSIX real-time signals which are specified in POSIX.1b, or, IEEE Std 1003.1b-1993, for Real-time Extensions for POSIX compliant Operating Systems.… Read more

hwclock, the hardware clock query and set program

The hardware clock

There are two clocks in a Linux system, the hardware real time clock (RTC) and the Linux system time maintained by the kernel. In this tutorial, we will look at the hardware real time clock.

The hardware real time clock is an integrated circuit, a part of computer's hardware, powered by a battery and keeps on running even when the system is electrically switched off.… Read more