UNIX for Advanced & Expert Users

the usage of "ps"

I have a user , the login ID is "acc_usr" , the user is running a very large process in my system ,

#who -u acc_usr
acc_usr pts/19 Mar 11 10:30 00:12 4231 (192.168.0.1)

but if I ps the user PID , the process is in "S" mode,
#ps -aux |grep 4231

root 4 231 0.0 0.0 2352 992 ? S 10:30 0:00 login -- acc_usr
acc_usr 319 0.0 0.0 3588 632 pts/22 S 11:51 0:00 grep 4231


I check with the command "top" , the user is running process , and in "R" mode , could suggest why ps can't find the "R" mode process , do I need to use other parameter ? thx.

Assuming I get what you want -
when you are executing ps, you have the cpu, acc_usr does not. Since acc_usr does not have the cpu he must be in sleep mode or whatever. Just not in run mode.

As long as you have the process id correct, you have the correct process. Don't worry about the state of the process.