count number of processes

imaso001 · 07-27-2016, 04:40 PM

What command would you enter to count the number of
processes running under your account?

I have tried these commands so far:

ps -Af | grep emacs | grep -v grep | wc -l

it tells me to "Use 'grep' to select lines containing your name"

ps -Af |grep -c emacs

it tells me to " Use 'grep' to select lines containing your name."

ps -Af | grep emacs | wc -l
it tells me to " Use 'grep' to select lines containing your name."

No luck with any of these please help!

suicidaleggroll · 07-27-2016, 05:03 PM

Quote:

Originally Posted by imaso001

What command would you enter to count the number of
processes running under your account?

I have tried these commands so far:

ps -Af | grep emacs | grep -v grep | wc -l

Why would you grep for emacs? That doesn't match the problem description at all.

Quote:

Originally Posted by imaso001

it tells me to "Use 'grep' to select lines containing your name"

What is "it", and why haven't you followed "it"'s instructions to grep for your user name instead of "emacs"?

imaso001 · 07-27-2016, 05:07 PM

My terminal l am putting the commands in, my teacher has it set up to where it tells me if the answer is correct or wrong.

jpollard · 07-27-2016, 05:54 PM

read the ps man page...
read the tail man page (though you might miss the part you need)
read the wc man page

RockDoctor · 07-28-2016, 02:13 PM

Look carefully at the output of your ps command, and read the man page for grep. The information you need is in the man page

Fred Caro · 07-30-2016, 09:22 PM

Quote:

read the tail man page

How would you instigate this on the cmd line?

Fred

jpollard · 07-30-2016, 09:47 PM

Were you sleep in class? The man command should have been given on the first day.

RockDoctor · 07-31-2016, 11:38 AM

Quote:

Originally Posted by Fred Caro

How would you instigate this on the cmd line?

Fred

I'd start by googling how to use google search from the command line. Once I received that result, I'd open a terminal window and, using what I learned previously to do that from the command line, google how to read the man page for tail.

I hope I didn't misunderstand your question

Fred Caro · 07-31-2016, 08:41 PM

Quote:

How would you instigate this on the cmd line?

My point is that this kind help is not very helpful.

The crux of the issue is displaying a count of processes for his account, don't know where he got "emacs" from.

Note as already said "man ps" gives some illumination:

Quote:

ps -aux myaccount

returns an error

This is not clear behavior as detailed in the man page

Also there is a difference between BSD ps and GNU.

Fred.

pan64 · 08-01-2016, 03:55 AM

Fred Caro and imaso001 are the same user?

Quote:

This is not clear behavior as detailed in the man page

would be nice to know what is unclear.

Also I'm not really sure about what do you really need.

gknetw · 08-01-2016, 05:42 AM

ps -u $USER | wc -l

jpollard · 08-01-2016, 07:36 AM

It WAS a homework assignment...

Which was why we were trying to get the OP to read the man pages.

Fred Caro · 08-01-2016, 08:09 PM

No fred caro is not the same "user" as imaso001 and the homework thing why I (fred) did not just give the answer.

But since an answer has been given, note also that:

Quote:

ps -aux fred

gives a warning or "error" but

Quote:

ps -au fred

does not.

this is partly explained in the ps man page but people find man pages difficult to interpret and telling people just too read the man page rather than a pointer as well as a (or many) man page[s] is not as helpful.

Fred.

jpollard · 08-02-2016, 05:52 AM

Quote:

Originally Posted by Fred Caro

this is partly explained in the ps man page but people find man pages difficult to interpret and telling people just too read the man page rather than a pointer as well as a (or many) man page[s] is not as helpful.

Fred.

The way you learn is to read the man page, then try the options out to see if it does what you think.

And telling people to read the documentation IS the most helpful.

pan64 · 08-03-2016, 10:29 AM

Quote:

Originally Posted by jpollard

The way you learn is to read the man page, then try the options out to see if it does what you think.

And telling people to read the documentation IS the most helpful.

Just a comment to this:
I read always the man page first, if something is unclear or some unexpected thing happened. This is really the first source to understand what's happening. So I think it is not a bad idea at all.