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NAME

skill, snice - send a signal or report process status

SYNOPSIS

skill [signal to send] [options] process selection criteria
snice [new priority] [options] process selection criteria

DESCRIPTION

These tools are probably obsolete and unportable. The command syntax is poorly defined. Consider using the killall, pkill, and pgrep commands instead.

The default signal for skill is TERM. Use -l or -L to list available signals. Particularly useful signals include HUP, INT, KILL, STOP, CONT, and 0. Alternate signals may be specified in three ways: -9 -SIGKILL -KILL.

The default priority for snice is +4. (snice +4 ...) Priority numbers range from +20 (slowest) to -20 (fastest). Negative priority numbers are restricted to administrative users.

GENERAL OPTIONS

-f fast mode This is not currently useful.
-i interactive use You will be asked to approve each action.
-v verbose output Display information about selected processes.
-w warnings enabled This is not currently useful.
-n no action This only displays the process ID.
-V show version Displays version of program.

PROCESS SELECTION OPTIONS

Selection criteria can be: terminal, user, pid, command. The options below may be used to ensure correct interpretation. Do not blame Albert for this interesting interface.

-t The next argument is a terminal (tty or pty).
-u The next argument is a username.
-p The next argument is a process ID number.
-c The next argument is a command name.

SIGNALS

The signals listed below may be available for use with skill. When known, numbers and default behavior are shown.

Name Num Action Description
0 0 n/a exit code indicates if a signal may be sent
ALRM 14 exit
HUP 1 exit
INT 2 exit
KILL 9 exit this signal may not be blocked
PIPE 13 exit
POLL exit
PROF exit
TERM 15 exit
USR1 exit
USR2 exit
VTALRM exit
STKFLT exit may not be implemented
PWR ignore may exit on some systems
WINCH ignore
CHLD ignore
URG ignore
TSTP stop may interact with the shell
TTIN stop may interact with the shell
TTOU stop may interact with the shell
STOP stop this signal may not be blocked
CONT restart continue if stopped, otherwise ignore
ABRT 6 core
FPE 8 core
ILL 4 core
QUIT 3 core
SEGV 11 core
TRAP 5 core
SYS core may not be implemented
EMT core may not be implemented
BUS core core dump may fail
XCPU core core dump may fail
XFSZ core core dump may fail

EXAMPLES

Command Description
snice seti crack +7 Slow down seti and crack
skill -KILL -v /dev/pts/* Kill users on new-style PTY devices
skill -STOP viro lm davem Stop 3 users
snice -17 root bash Give priority to root's shell

SEE ALSO

killall(1) pkill(1) kill(1) renice(1) nice(1) signal(7) kill(2)

STANDARDS

No standards apply.

AUTHOR

Albert Cahalan <albert@users.sf.net> wrote skill and snice in 1999 as a replacement for a non-free version, and is the current maintainer of the procps collection. Please send bug reports to <procps-feedback@lists.sf.net>.