SKILL(1)

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>.