siginterrupt(3C)

siginterrupt -- allow signals to interrupt system calls

Synopsis

   #include <signal.h>
   
   int siginterrupt(int sig, int flag);

Description

The siginterrupt function is used to change the restart behaviour when a function is interrupted by the specified signal.

If the flag is true (1), then system calls will be restarted if they are interrupted by the specified signal and no data has been transferred yet.

If the flag is false (0), then restarting of system calls is disabled. If a system call is interrupted by the specified signal and no data has been transferred, the system call will return -1 with errno set to EINTR. Interrupted system calls that have started transferring data will return the amount of data actually transferred.

Issuing a siginterrupt call during the execution of a signal handler will cause the new action to take place on the next signal to be caught.

Return values

A 0 value indicates that the call succeeded. A -1 value indicates that an invalid signal number has been supplied.

Errors

The siginterrupt function will fail if:

EINVAL: The sig argument is not a valid signal number.

Compatibility

The siginterrupt function supports programs written to historical system interfaces. A portable application, when being written or rewritten, should use sigaction(2) with the SA_RESTART flag instead of siginterrupt.

References

sigaction(2), signal(2)

Standards conformance

This routine conforms to X/Open System Interfaces and Headers, Issue 4, Version 2.