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sigsuspend(2) [osf1 man page]

sigsuspend(2)							System Calls Manual						     sigsuspend(2)

NAME
sigsuspend - Atomically changes the set of blocked signals and waits for a signal LIBRARY
Standard C Library (libc.so, libc.a) SYNOPSIS
#include <signal.h> int sigsuspend ( const sigset_t *signal_mask ); STANDARDS
Interfaces documented on this reference page conform to industry standards as follows: sigsuspend(): XPG4, XPG4-UNIX Refer to the standards(5) reference page for more information about industry standards and associated tags. PARAMETERS
Points to a set of signals. DESCRIPTION
The sigsuspend() function replaces the signal mask of the process (or thread) with the set of signals pointed to by the signal_mask parame- ter, and then suspends execution of the caller until delivery of a signal whose action is either to execute a signal-catching function or to terminate the process. The sigsuspend() function does not allow the SIGKILL or SIGSTOP signals to be blocked. If a program attempts to block one of these signals, the sigsuspend() function gives no indication of the error; the illegal request is simply ignored. If delivery of a signal causes the process to terminate, the sigsuspend() function does not return. If delivery of a signal causes a sig- nal-catching function to execute, the sigsuspend() function returns after the signal-catching function returns, with the signal mask restored to the set that existed prior to the call to the sigsuspend() function. The sigsuspend() function sets the signal mask and waits for an unblocked signal as one atomic operation. This means that signals cannot occur between the operations of setting the mask and waiting for a signal. If a program invokes sigprocmask(SIG_SETMASK) and sigpause() separately, a signal that occurs between these functions might not be noticed by sigpause(). In normal usage, a signal is blocked by using the sigprocmask(SIG_BLOCK,...) or pthread_sigmask(...) function at the beginning of a crit- ical section. The process then determines whether there is work for it to do. If no work is to be done, the process waits for work by call- ing the sigsuspend() function with the mask previously returned by the sigprocmask() function. NOTES
The sigpause() function is provided for compatibility with older UNIX systems; its function is a subset of the sigsuspend() function. RETURN VALUES
Since the sigsuspend() function suspends process execution indefinitely, there is no successful completion return value. If a return occurs, -1 is returned and errno is set to indicate the error. ERRORS
The sigsuspend() function sets errno to the specified values for the following conditions: A signal is caught by the calling process and control is returned from the signal-catching function. RELATED INFORMATION
Functions: pause(3), sigaction(2), sigblock(2), sigprocmask(2), sigvec(2) Standards: standards(5) delim off sigsuspend(2)

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sigpause(3)						     Library Functions Manual						       sigpause(3)

NAME
sigpause - Provides a compatibility interface to the sigsuspend function LIBRARY
Standard C Library (libc.so, libc.a) SYNOPSIS
#include <signal.h> int sigpause ( int signal_mask ); STANDARDS
Interfaces documented on this reference page conform to industry standards as follows: sigpause(): XSH4.2 Refer to the standards(5) reference page for more information about industry standards and associated tags. PARAMETERS
Specifies which signals to block. DESCRIPTION
The sigpause() function call blocks the signals specified by the signal_mask parameter and then suspends execution of the process until delivery of a signal whose action is either to execute a signal-catching function or to end the process. Signal of value i is blocked if the i-th bit of the mask is set. Only signals with values 1 to 31 can be blocked with the sigpause() function. In addition, the sigpause() function does not allow the SIGKILL, SIGSTOP, or SIGCONT signals to be blocked. If a program attempts to block one of these signals, the sigpause() function gives no indication of the error. The sigpause() function sets the signal mask and waits for an unblocked signal as one atomic operation. This means that signals cannot occur between the operations of setting the mask and waiting for a signal. The sigpause() function is provided for compatibility with older UNIX systems; its function is a subset of the sigsuspend() function. NOTES
[Tru64 UNIX] When compiled in the X/Open UNIX environment, calls to the sigpause() function are internally renamed by prepending _E to the function name. When you are debugging a module that includes the sigpause() function and for which _XOPEN_SOURCE_EXTENDED has been defined, use _Esigpause to refer to the sigpause() call. See standards(5) for information on when the _XOPEN_SOURCE_EXTENDED macro is defined. RETURN VALUES
Upon successful completion, sigpause() returns 0 (zero). Otherwise, -1 is returned and errno is set to indicate the error. ERRORS
The sigpause() function sets errno to the specified values for the following conditions: The signal_mask parameter refers to an illegal signal number. [Tru64 UNIX] A signal was caught by the calling process. RELATED INFORMATION
Functions: pause(3), sigaction(2), sigblock(2), sigprocmask(2), sigsuspend(2), sigvec(2) Standards: standards(5) delim off sigpause(3)
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