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skill - Unix, Linux Command


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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

-ffast modeThis is not currently useful.
-iinteractive useYou will be asked to approve each action.
-vverbose outputDisplay information about selected processes.
-wwarnings enabledThis is not currently useful.
-nno actionThis only displays the process ID.
-Vshow versionDisplays 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.
-tThe next argument is a terminal (tty or pty).
-uThe next argument is a username.
-pThe next argument is a process ID number.
-cThe 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.
NameNumActionDescription
00n/aexit code indicates if a signal may be sent
ALRM14exit 
HUP1exit 
INT2exit 
KILL9exitthis signal may not be blocked
PIPE13exit 
POLL exit 
PROF exit 
TERM15exit 
USR1 exit 
USR2 exit 
VTALRM exit 
STKFLT exitmay not be implemented
PWR ignoremay exit on some systems
WINCH ignore 
CHLD ignore 
URG ignore 
TSTP stopmay interact with the shell
TTIN stopmay interact with the shell
TTOU stopmay interact with the shell
STOP stopthis signal may not be blocked
CONT restartcontinue if stopped, otherwise ignore
ABRT6core 
FPE8core 
ILL4core 
QUIT3core 
SEGV11core 
TRAP5core 
SYS coremay not be implemented
EMT coremay not be implemented
BUS corecore dump may fail
XCPU corecore dump may fail
XFSZ corecore dump may fail

EXAMPLES

CommandDescription
snice seti crack +7Slow down seti and crack
skill -KILL -v /dev/pts/*Kill users on new-style PTY devices
skill -STOP viro lm davemStop 3 users
snice -17 root bashGive priority to root’s shell

SEE ALSO

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>.

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