The role of Linux Sa_restart

Sa_restart is used when setting a signal processing function for a signal to set a marker for the signal.

In general, a process is executing a system call, and the signal is not delivered until the system call returns. Except for slow system calls, such as read-write terminals, networks, disks, and wait and pause. These system calls will return -1,errno to EINTR when the system call is interrupted, we can choose to invoke it again using a loop, or set a restart for the system call (Sa_restart).

Once a Sa_restart token is set for the signal, when a blocking system call is executed, the process does not return, but the system call is re-executed.

The role of Linux Sa_restart