NAME

Psignal — set signal tracing action

LIBRARY

Process Control Library (libproc, -lproc)

SYNOPSIS

#include <libproc.h>

int
Psignal(struct ps_prochandle *P, int which, int stop);

DESCRIPTION

The Psignal() function sets the signal tracing flag for the process handle P. If stop is non-zero it causes the process handle to stop threads that encounter the signal which. If stop is zero, then it disables tracing for the signal which.

The signal constants, representing valid values for which, can be found in signal.h(3HEAD). The signal SIGKILL may not be stopped.

Note, only active processes may have their signal tracing flags updated. Process handles that refer to core files, zombie processes, and files do not have signal tracing flags. Calling this function on them is an error.

RETURN VALUES

Upon successful completion, the Psignal() function returns the previous disposition of the signal which. It returns 1 if it was set and 0 if not. Otherwise, -1 is returned and errno is set to indicate the error.

ERRORS

The Psignal() function will fail if:

EINVAL: which is SIGKILL and stop is non-zero .
which is not a valid signal.
ENOENT: P does not correspond to an active process.

INTERFACE STABILITY

Uncommitted

MT-LEVEL

See LOCKING in libproc(3LIB).