probe::signal.send.return (3stap)

signal.send.return

retstr

The return value to either __group_send_sig_info, specific_send_sig_info, or send_sigqueue

name

The name of the function used to send out the signal

send2queue

Indicates whether the sent signal was sent to an existing sigqueue

shared

Indicates whether the sent signal is shared by the thread group.

The signal's sender. (correct?)

Possible __group_send_sig_info and specific_send_sig_info return values are as follows;

0 -- The signal is successfully sent to a process, which means that, (1) the signal was ignored by the receiving process, (2) this is a non-RT signal and the system already has one queued, and (3) the signal was successfully added to the sigqueue of the receiving process.

-EAGAIN -- The sigqueue of the receiving process is overflowing, the signal was RT, and the signal was sent by a user using something other than kill.

Possible send_group_sigqueue and send_sigqueue return values are as follows;

0 -- The signal was either successfully added into the sigqueue of the receiving process, or a SI_TIMER entry is already queued (in which case, the overrun count will be simply incremented).

1 -- The signal was ignored by the receiving process.

-1 -- (send_sigqueue only) The task was marked exiting, allowing * posix_timer_event to redirect it to the group leader.