#!/bin/bash

Signal numbers to use. Configurable, as long as the number of elements in this

array matches the number of elements in $delays.

signals=(15 2 1 9)

How much time processes should be given to finish their work before we try the

next signal. Configurable, as long as the number of elements in this array

matches the number of elements in $signals.

delays=(2 3 4 0)

Takes a list of PIDs and ends the processes through increasingly rude means.

function mykill { # Cygwin's default ps is gimped. Use the GNU version instead. local ps='ps' if [[ $(uname -o) == 'Cygwin' ]]; then ps='procps' fi ps="$ps o pid="

# Figure out the names of the signals we will try.
local names=($(kill -l ${signals[@]}))

local retval=0
if [[ $# -eq 0 ]]; then
    printf 'mykill: Too few arguments: %d\nmykill: Usage: mykill <PIDs...>\n' $#
    retval=1
else
    for pid in $@; do
        local index=0
        # Try the next signal if the process is alive AND there are more
        # signals to attempt AND the previous kill reported no errors.
        while $ps $pid > /dev/null && [[ $index -lt ${#signals} ]] && [[ $retval -eq 0 ]]; do
            output=$(kill -s ${signals[$index]} $pid 2>&1)
            retval=$?
            local killed=1
            # Give the process some time to finish.
            sleep ${delays[$index]}
            index=$(($index + 1))
        done

        if [[ -z $killed ]]; then
            printf 'mykill: Process with PID %d does not exist.\n' $pid

        elif ! ${ps} ${pid} > /dev/null; then
            index=$(($index - 1))
            printf 'mykill: Killed process with PID %d with signal %s (%d).\n' $pid ${names[$index]} ${signals[$index]}

        elif [[ ${retval} -ne 0 ]]; then
            printf 'mykill: kill failed: %s\n' $(echo ${output} | cut -d ' ' -f 5-)

        elif [[ ${index} -eq ${#signals} ]]; then
            printf 'mykill: Failed to kill process with PID %d with signals %s\n' $pid "$(echo ${names[@]})"
            retval=-1
        fi
    done
fi
return ${retval}

}

mykill $@