除非你正在运行的 BSD PS ，你应该能够使用 -C 标记或指派，

Unless you're running BSD ps, you should be able to use a -C flag or pgrep

-C cmdlist      Select by command name. This selects the processes whose executable 
                name is given in cmdlist.

例如，

if ps -C node > /dev/null
then
        date > /etc/nodeCheck.log 
else
        date > /dev/null 
fi

或

if pgrep node > /dev/null
then
        date > /etc/nodeCheck.log 
else
        date > /dev/null 
fi