How to get to know whether the Linux process is running

Question

Given a pid, for example 29264， how to get to know whether the process is running ?

Is there any easy way to do that ?

thx

Answer 1

Process status ( ps ) provides the information you're looking for:

ps -p 29264

Output in case the process is running (quick example on my Mac, works the same on Linux):

PID     TIME       CMD
127     4:54.03    /System/Library/CoreServices/Finder.app/Contents/MacOS/Finder

Otherwhise:

PID     TIME       CMD

Answer 2

kill -0 29264 ,and inspect the error (if any)

Answer 3

获取过程状态：

ps -p 29264 > /dev/null; echo $?