用于检查进程是否已在运行的Shell脚本,如果是,则退出

Question

我有一个shell脚本,方法status()和start().代码如下:

#function to check the jmeter processes running
status(){
     PID=$(ps -ef | grep jmeter|grep -v grep)
     echo "The jmeter processes running are: \n$PID"
}

#function to run the .jmx file given by the user at run time
start(){
     echo "Please enter the file name .jmx extension"
     read file
     echo "Please enter the log file name .jtl extension"
     read log_file
     sh /home/ubuntu/apache-jmeter-3.0/bin/jmeter.sh -n -t $file -l $log_file &
}
while [ "$1" != "" ]; do
case "$1" in
        start)
            jmeter_start
            ;;
         status)
            jmeter_status
            ;;
          *)
            echo $"Usage: $0 {start|status}"
            exit 1
        esac
   shift
done

现在当我运行这个脚本时,我必须检查它是否已经在运行,如果它正在运行,我必须退出.让我知道如何做到这一点.

Answer 1

在函数的开头添加一个标志并将其设置为1，在函数的结尾处将其设置为0，随意查询。

#function to check the jmeter processes running
status(){
     PID=$(ps -ef | grep jmeter|grep -v grep)
     echo "The jmeter processes running are: \n$PID"
}

#function to run the .jmx file given by the user at run time
start(){
     export start_flag=1
     echo "Please enter the file name .jmx extension"
     read file
     echo "Please enter the log file name .jtl extension"
     read log_file
     sh /home/ubuntu/apache-jmeter-3.0/bin/jmeter.sh -n -t $file -l $log_file &
     export start_flag=0
}

另一种选择是写入外部文件并查询它。