Open System Services Library Calls Reference Manual (G06.29+, H06.08+, J06.03+)

OSS Library Calls (s) sigdelset(3)
NAME
sigdelset - Deletes a signal from a signal set
LIBRARY
G-series native OSS processes: system library
H-series and J-series OSS processes: implicit libraries
SYNOPSIS
#include <signal.h>
int sigdelset(
sigset_t *set,
int sig_number );
PARAMETERS
set Points to the signal set to be modified.
sig_number Specifies the signal to be deleted from the set.
DESCRIPTION
The sigdelset( ) function deletes the individual signal specified by the sig_number parameter
from the signal set pointed to by the set parameter.
This function operates on data objects that can be addressed by the application, not on any set of
signals known to the system. This function is not for operating on the set of signals blocked from
delivery to a process or the set pending for a process.
A call to either the sigfillset( ) or sigemptyset( ) function must be made at least once for each
object of the type sigset_t before the sigdelset( ) function is used on that set. If the object is used
without such initialization, the results are undefined.
RETURN VALUES
Upon successful completion, the sigdelset( ) function returns the value 0 (zero). If an error is
detected, the value -1 is returned, and errno is set to indicate the error.
ERRORS
If any of the following conditions occurs, the sigdelset( ) function sets errno to the correspond-
ing value:
[EFAULT] The set parameter points to a location outside the allocated address space of the
process.
[EINVAL] The value of the sig_number parameter is an invalid or unsupported signal
number.
RELATED INFORMATION
Functions: sigaction(2), sigaddset(3), sigemptyset(3), sigfillset(3), sigismember(3), sigproc-
mask(2), sigsuspend(2).
Files: signal(4).
STANDARDS CONFORMANCE
The POSIX standards leave some features to the implementing vendor to define. The following
features are affected in the HP implementation:
• Use of this function on a signal set that has not been properly initialized causes
undefined results.
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