Table of Contents
What is a Sigset?
General description. The sigset() function provides a simplified method for changing the action associated with a specific signal and unblock the signal, or to block this signal. sig. The number of a recognized signal.
What is Sigaction in C?
The sigaction() function allows the calling process to examine and/or specify the action to be associated with a specific signal.
What is Sigemptyset in C?
sigemptyset() is part of a family of functions that manipulate signal sets. Signal sets are data objects that let a process keep track of groups of signals. For example, a process can create one signal set to record which signals it is blocking, and another signal set to record which signals are pending.
What type is Sigset_t?
The sigset_t data type is used to represent a signal set. Internally, it may be implemented as either an integer or structure type. For portability, use only the functions described in this section to initialize, change, and retrieve information from sigset_t objects—don’t try to manipulate them directly.
Does Sigwait block?
The signals defined by set are required to be blocked at the time of the call to sigwait(); otherwise, sigwait() is not successful, and an [EINVAL] error is returned. The signals SIGKILL or SIGStop cannot be selected. Any attempt to use sigwait() to select these signals is simply ignored, and no error is returned.
Can Sigemptyset fail?
If successful, sigemptyset() returns a value of zero. On failure, it returns a value of -1 and sets errno to one of the following values: EFAULT. set is an invalid pointer.
What is Sigsuspend?
The sigsuspend() function replaces the current signal mask of a thread with the signal set given by *sigmask and then suspends processing of the calling process.
Can SIGStop be masked?
The sigprocmask() function examines, or changes, or both examines and changes the signal mask of the calling thread. The signals SIGKILL or SIGStop cannot be blocked. Any attempt to use sigprocmask() to block these signals is simply ignored, and no error is returned.
What does Sigwait return?
The sigwait() function selects a pending signal from set, clears it from the set of pending signals for the thread or process, and returns that signal number in the location that is referenced by sig.
Are signal handler inherited?
Signal handlers are inherited. This means the children inherit the same handlers as the parent has.
What is the difference between sigaction and signal?
The signal() function does not (necessarily) block other signals from arriving while the current handler is executing; sigaction() can block other signals until the current handler returns. The signal() function (usually) resets the signal action back to SIG_DFL (default) for almost all signals.
What are the advantages of sigaction over signal?