pskill
Kill a Process
Description
pskill
sends a signal to a process, usually to terminate it.
Usage
pskill(pid, signal = SIGTERM) SIGHUP SIGINT SIGQUIT SIGKILL SIGTERM SIGSTOP SIGTSTP SIGCHLD SIGUSR1 SIGUSR2
Arguments
pid | positive integers: one or more process IDs as returned by |
signal | integer, most often one of the symbolic constants. |
Details
Signals are a C99 concept, but only a small number are required to be supported (of those listed, only SIGINT
and SIGTERM
). They are much more widely used on POSIX operating systems (which should define all of those listed here), which also support a kill
system call to send a signal to a process, most often to terminate it. Function pskill
provides a wrapper: it silently ignores invalid values of its arguments, including zero or negative pids.
In normal use on a Unix-alike, Ctrl-C sends SIGINT
, Ctrl-\ sends SIGQUIT
and Ctrl-Z sends SIGTSTP
: that and SIGSTOP
suspend a process which can be resumed by SIGCONT
.
The signals are small integers, but the actual numeric values are not standardized (and most do differ between OSes). The SIG*
objects contain the appropriate integer values for the current platform (or NA_INTEGER_
if the signal is not defined).
Only SIGINT
and SIGKILL
will be defined on Windows, and pskill
will always use the Windows system call TerminateProcess
.
Value
A logical vector of the same length as pid
, TRUE
(for success) or FALSE
, invisibly.
See Also
Package parallel has several means to launch child processes which record the process IDs.
Examples
## Not run: pskill(c(237, 245), SIGKILL) ## End(Not run)
Copyright (©) 1999–2012 R Foundation for Statistical Computing.
Licensed under the GNU General Public License.