GSP
Quick Navigator

Search Site

Unix VPS
A - Starter
B - Basic
C - Preferred
D - Commercial
MPS - Dedicated
Previous VPSs
* Sign Up! *

Support
Contact Us
Online Help
Handbooks
Domain Status
Man Pages

FAQ
Virtual Servers
Pricing
Billing
Technical

Network
Facilities
Connectivity
Topology Map

Miscellaneous
Server Agreement
Year 2038
Credits
 

USA Flag

 

 

Man Pages


Manual Reference Pages  -  GSIGNAL (9)

NAME

psignal, kern_psignal, pgsignal, gsignal, tdsignal - post signal to a thread, process, or process group

CONTENTS

Synopsis
Description
See Also
History

SYNOPSIS


.In sys/types.h
.In sys/signalvar.h void kern_psignal struct proc *p int signum void pgsignal struct pgrp *pgrp int signum int checkctty void gsignal int pgid int signum void tdsignal struct thread *td int signum

DESCRIPTION

These functions post a signal to a thread or one or more processes. The argument signum common to all three functions should be in the range [1- NSIG].

The kern_psignal function posts signal number signum to the process represented by the process structure p. The kern_psignal function used to be called psignal but was renamed in order to eliminate a name collision with the libc function of that name and facilitate code reuse. With a few exceptions noted below, the target process signal disposition is updated and is marked as runnable, so further handling of the signal is done in the context of the target process after a context switch. Note that kern_psignal does not by itself cause a context switch to happen.

The target process is not marked as runnable in the following cases:

  • The target process is sleeping uninterruptibly. The signal will be noticed when the process returns from the system call or trap.
  • The target process is currently ignoring the signal.
  • If a stop signal is sent to a sleeping process that takes the default action (see sigaction(2)), the process is stopped without awakening it.
  • SIGCONT restarts a stopped process (or puts them back to sleep) regardless of the signal action (e.g., blocked or ignored).

If the target process is being traced kern_psignal behaves as if the target process were taking the default action for signum. This allows the tracing process to be notified of the signal.

The pgsignal function posts signal number signum to each member of the process group described by pgrp. If checkctty is non-zero, the signal will be posted only to processes that have a controlling terminal. pgsignal is implemented by walking along the process list headed by the field pg_members of the process group structure pointed at by pgrp and calling kern_psignal as appropriate. If pgrp is NULL no action is taken.

The gsignal function posts signal number signum to each member of the process group identified by the group id pgid. gsignal first finds the group structure associated with pgid, then invokes pgsignal with the argument checkctty set to zero. If pgid is zero no action is taken.

The tdsignal function posts signal number signum to the thread represented by the thread structure td.

SEE ALSO

sigaction(2), signal(9), tsleep(9)

HISTORY

The psignal function was renamed to kern_psignal in
.Fx 9.0 .
Search for    or go to Top of page |  Section 9 |  Main Index


Powered by GSP Visit the GSP FreeBSD Man Page Interface.
Output converted with manServer 1.07.