Script para execução de atividades no Cron, com controle de horas e bloqueio de múltiplas execuções. Rode com cron_script.sh <path da atividade>.

cron_script.sh

#!/usr/bin/env bash

## Script Modelo de execução de tarefas no cron
## Recomendação: Usar script na pasta /etc/cron.d/ em vez de usar cron de usuário (crontab -e)
## Recomendação: Usar rotação de logs (https://www.thegeekstuff.com/2010/07/logrotate-examples)

##################################################### Configuração ####################################################
#TODO: Criar /etc/logrotate.d/script

if [ $# -ne 1 ]; then
    echo "Uso: $0 <path do script>"
    exit 1
else
    SCRIPT_PATH=$1
    SCRIPT_NOME="$(basename ${SCRIPT_PATH})"
fi

SCRIPT_LOG=/var/log/cron-${SCRIPT_NOME}.log
touch ${SCRIPT_LOG}

############################################## Rotinas de Lock do Script ##############################################

SCRIPT_LOCK=/tmp/${SCRIPT_NOME}.lock
PIDFILE=${SCRIPT_LOCK}/PID
UNLOCK_V=0
P1=-1

echo "PID: $$."

function lock {
	mkdir ${SCRIPT_LOCK} &> /dev/null
	if [ $? == 0 ]; then
		echo $$ > ${PIDFILE}
		echo "Lock."
	else
		PID=$(cat $PIDFILE)
		echo "Lock detectado. PID do Lock: ${PID}"
		kill -0 ${PID} &>/dev/null
		if [ $? != 0 ]; then
			echo "Processo ${PID} inexistente. Limpando."
			unlock
			echo "Reiniciando script."
			exec "$0" "$@"
		else
			echo "Outra instância rodando. Abortando."
			UNLOCK_V=1
			exit 1
		fi
	fi
}

function unlock {
	echo "Unlock."
	rm -rf ${SCRIPT_LOCK}
}

function exit_end {
	echo "Exit."
	if [ ${UNLOCK_V} == 0 ]; then
		unlock
		UNLOCK_V=1
	fi
	if [ ${P1} != -1 ]; then
		kill -TERM "${P1}" &>/dev/null
	fi
	exit $1
}

trap 'exit_end $?' KILL ERR QUIT TERM EXIT INT

lock

######################################################### Log #########################################################

# Registro de início da atividade
INICIO_T="$(date +'%d-%m-%Y às %H:%M:%S')"
echo "####################################" >> ${SCRIPT_LOG}
echo "### Execução agendada do script ${0}." >> ${SCRIPT_LOG}
echo "### Início: $INICIO_T" >> ${SCRIPT_LOG}
echo "------------------------------------" >> ${SCRIPT_LOG}

time (
####################################################### Script ########################################################
${SCRIPT_PATH}
####################################################### Script ########################################################
) &>> ${SCRIPT_LOG} &

P1=$!
wait ${P1}
P1=-1

echo "Carga: $(cut -d ' ' -f1,2,3 /proc/loadavg)" >> ${SCRIPT_LOG}

# Registro de fim da atividade
FIM_T="$(date +'%d-%m-%Y às %H:%M:%S')"
echo "------------------------------------" >> ${SCRIPT_LOG}
echo "### Término: ${FIM_T}." >> ${SCRIPT_LOG}
echo "####################################" >> ${SCRIPT_LOG}
echo >> ${SCRIPT_LOG}

teste.sh

#!/usr/bin/env bash

sleep 2
echo 1
sleep 2
echo 2
sleep 2
ls -la
sleep 2
echo 3
sleep 2
echo 4
sleep 2