Linux判断进程是否存在并启动该进程

#!/bin/bash
#判断进程是否存在，如果不存在就启动它
PIDS=`ps -ef |grep myprocess |grep -v grep | awk '{print $2}'`
if [ "$PIDS" != "" ]; then
echo "myprocess is runing!"
else
cd /root/
./myprocess
#运行进程
fi

 grep -v grep命令：去除包含grep的进程行 ，避免影响最终数据的正确性 。

[root@CENTOS57 eq]# ps -ef |grep led
root       9240   1562  0 Oct22 pts/0    00:01:09 ./ledThread ledall
root       9809   1562  0 06:41 pts/0    00:00:00 grep --color=auto led

[root@CENTOS57 eq]# ps -ef |grep led |grep -v grep
root       9240   1562  0 Oct22 pts/0    00:01:09 ./ledThread ledall

[root@CENTOS57 eq]# ps -ef |grep led |grep -v grep | awk '{print $2}'
9240