SIGSEND(2) System Calls SIGSEND(2)

NAME

sigsend, sigsendset - send a signal to a process or a group of
processes

SYNOPSIS

#include <signal.h>

int sigsend(idtype_t idtype, id_t id, int sig);


int sigsendset(procset_t *psp, int sig);

DESCRIPTION

The sigsend() function sends a signal to the process or group of
processes specified by id and idtype. The signal to be sent is
specified by sig and is either 0 or one of the values listed in
signal.h(3HEAD). If sig is 0 (the null signal), error checking is
performed but no signal is actually sent. This value can be used to
check the validity of id and idtype.


The real or effective user ID of the sending process must match the
real or saved user ID of the receiving process, unless the
{PRIV_PROC_OWNER} privilege is asserted in the effective set of the
sending process or sig is SIGCONT and the sending process has the
same session ID as the receiving process.


If idtype is P_PID, sig is sent to the process with process ID id.


If idtype is P_PGID, sig is sent to all processes with process group
ID id.


If idtype is P_SID, sig is sent to all processes with session ID id.


If idtype is P_TASKID, sig is sent to all processes with task ID id.


If idtype is P_UID, sig is sent to any process with effective user
ID id.


If idtype is P_GID, sig is sent to any process with effective group
ID id.


If idtype is P_PROJID, sig is sent to any process with project ID
id.


If idtype is P_CID, sig is sent to any process with scheduler class
ID id (see priocntl(2)).


If idtype is P_CTID, sig is sent to any process with process
contract ID id.


If idtype is P_ALL, sig is sent to all processes and id is ignored.


If id is P_MYID, the value of id is taken from the calling process.


The process with a process ID of 0 is always excluded. The process
with a process ID of 1 is excluded unless idtype is equal to P_PID.


The sigsendset() function provides an alternate interface for sending
signals to sets of processes. This function sends signals to the set
of processes specified by psp. psp is a pointer to a structure of
type procset_t, defined in <sys/procset.h>, which includes the
following members:

idop_t p_op;
idtype_t p_lidtype;
id_t p_lid;
idtype_t p_ridtype;
id_t p_rid;


The p_lidtype and p_lid members specify the ID type and ID of one
("left") set of processes; the p_ridtype and p_rid members specify
the ID type and ID of a second ("right") set of processes. ID types
and IDs are specified just as for the idtype and id arguments to
sigsend(). The p_op member specifies the operation to be performed on
the two sets of processes to get the set of processes the function is
to apply to. The valid values for p_op and the processes they specify
are:

POP_DIFF
Set difference: processes in left set and not in right
set.


POP_AND
Set intersection: processes in both left and right sets.


POP_OR
Set union: processes in either left or right set or both.


POP_XOR
Set exclusive-or: processes in left or right set but not
in both.

RETURN VALUES

Upon successful completion, 0 is return. Otherwise, -1 is returned
and errno is set to indicate the error.

ERRORS

The sigsend() and sigsendset() functions will fail if:

EINVAL
The sig argument is not a valid signal number, or the
idtype argument is not a valid idtype field.


EINVAL
The sig argument is SIGKILL, idtype is P_PID and id is 1
(proc1).


EPERM
The effective user of the calling process does not match
the real or saved user ID of the receiving process, the
calling process does not have the {PRIV_PROC_OWNER}
privilege asserted in the effective set, and the calling
process is not sending SIGCONT to a process that shares the
same session ID.

The calling process does not have the {PRIV_PROC_SESSION}
privilege asserted and is trying to send a signal to a
process with a different session ID, even though the
effective user ID matches the real or saved ID of the
receiving process.


ESRCH
No process can be found corresponding to that specified by
id and idtype.


The sigsendset() function will fail if:

EFAULT
The psp argument points to an illegal address.

SEE ALSO

kill(1), getpid(2), kill(2), priocntl(2), signal(3C),
signal.h(3HEAD), process(5), privileges(7)

July 19, 2004 SIGSEND(2)