Showing Running Processes in variable

Ruby
1

I want to capture the list of running processes on my computer. I am to
get all the data into my variable with a simple system call:

x = ps -el

My problem comes when I want to display the data back out in a legible
format that makes sense.

What is the best way to do this?

thanks

jackster

2

quoth the jackster the jackle:

I want to capture the list of running processes on my computer. I am to
get all the data into my variable with a simple system call:

x = ps -el

My problem comes when I want to display the data back out in a legible
format that makes sense.

What is the best way to do this?

Not sure if this is the best but:

x.split("\n").each do |line|
puts line
end

works for me.

thanks

jackster

-d

3

Thanks for the help Darren…what you proposed works but it doesn’t
print out the processes in a viewable table in rails…I think I
somehow need to add a “\n” or a line break to the result…This might
be a rails question now but just in case you might know, here is what I
have in my controller:

def processes
x=ps -el
y=x.split("\n")
y.each do |line|
end
return y
end

Then I simply display the variable in my view with: <%= processes() %>

Here is what the view looks like:

F S UID PID PPID C PRI NI ADDR SZ WCHAN TTY TIME CMD000 S 2202 11254 1 0
75 0 - 545 wait4 ? 00:00:00 mysqld_sa000 S 2202 11342 11254 0 80 5 -
5887 schedu ? 00:00:00 mysqld040 S 2202 11368 11342 0 80 5 - 5887 schedu
? 00:00:01 mysqld040 S 2202 11370 11368 0 80 5 - 5887 rt_sig ? 00:00:00
mysqld000 S 2202 22812 1 0 75 0 - 5744 schedu ? 00:00:00 dispatch.000 S
2202 23955 1 0 75 0 - 5322 schedu ? 00:00:00 dispatch.100 S 2202 23807
23691 0 75 0 - 579 schedu pts/4 00:00:00 sh000 T 2202 26309 23807 0 75 0

  • 1137 do_sig pts/4 00:00:00 irb040 S 2202 18127 1 2 75 0 - 6578 schedu
    ? 00:00:00 httpd040 S 2202 18132 18127 0 75 0 - 6299 schedu ? 00:00:00
    httpd040 S 2202 18172 18127 0 75 0 - 6605 schedu ? 00:00:00 httpd000 S
    2202 18178 18132 17 79 0 - 5475 pipe_w ? 00:00:00 dispatch.040 S 2202
    18185 18127 0 76 0 - 6581 schedu ? 00:00:00 httpd000 R 2202 18218 18178
    0 80 0 - 397 - ? 00:00:00 ps100 S 2202 18219 1475 0 77 0 - 503 wait4 ?
    00:00:00 sps000 R 2202 18235 18219 0 78 0 - 897 - ? 00:00:00 ps

Thanks again,

jackster

darren kirby wrote:

quoth the jackster the jackle:

I want to capture the list of running processes on my computer. I am to
get all the data into my variable with a simple system call:

x = ps -el

My problem comes when I want to display the data back out in a legible
format that makes sense.

What is the best way to do this?

Not sure if this is the best but:

x.split("\n").each do |line|
puts line
end

works for me.

thanks

jackster

-d

4

On 12/13/07, jackster the jackle [email protected] wrote:

Thanks for the help Darren…what you proposed works but it doesn’t
print out the processes in a viewable table in rails…I think I
somehow need to add a “\n” or a line break to the result…This might

I’m not a web guy, but… You need a
to generate a newline in html,
right?

The each statement does nothing there, and the return is redundant.
How about just

def processes
ps -el.gsub(/\n/,“
”)
end

-Adam

5

jackster the jackle wrote:

I want to capture the list of running processes on my computer. I am to
get all the data into my variable with a simple system call:

x = ps -el

My problem comes when I want to display the data back out in a legible
format that makes sense.

What is the best way to do this?

I recommend sys-proctable instead.

require ‘sys/proctable’
include Sys

ProcTable.ps do |process|
p process.cmdline
…
end

Regards,

Dan

6

Try this:

def view
@result = “”
x = ps -el
x.each_line do |l|
@result += l + “
”
end
return @result
end

I remembered that carriage return is always funny from system to system.
This should work.

Good luck!

jackster the jackle wrote:

I want to capture the list of running processes on my computer. I am to
get all the data into my variable with a simple system call:

x = ps -el

My problem comes when I want to display the data back out in a legible
format that makes sense.

What is the best way to do this?

thanks

jackster

7

Thanks for the replies but they don’t seem to work in Rails.

Dan,

Is sys/proctable a gem that I can install? …if so, do you have link?

thanks

jackster

Daniel B. wrote:

jackster the jackle wrote:

I want to capture the list of running processes on my computer. I am to
get all the data into my variable with a simple system call:

x = ps -el

My problem comes when I want to display the data back out in a legible
format that makes sense.

What is the best way to do this?

I recommend sys-proctable instead.

require ‘sys/proctable’
include Sys

ProcTable.ps do |process|
p process.cmdline
…
end

Regards,

Dan

8

I just tested it in Rails 2.0.1 with the following:

controller:

def view
@result = “”
x = ps -el
x.each_line do |l|
@result += l + “
”
end
return @result
end

model:

<= @result %>

What version of Rails are you using?

jackster the jackle wrote:

Thanks for the replies but they don’t seem to work in Rails.

Dan,

Is sys/proctable a gem that I can install? …if so, do you have link?

thanks

jackster

Daniel B. wrote:

jackster the jackle wrote:

I want to capture the list of running processes on my computer. I am to
get all the data into my variable with a simple system call:

x = ps -el

My problem comes when I want to display the data back out in a legible
format that makes sense.

What is the best way to do this?

I recommend sys-proctable instead.

require ‘sys/proctable’
include Sys

ProcTable.ps do |process|
p process.cmdline
…
end

Regards,

Dan

9

jackster the jackle wrote:

Thanks for the replies but they don’t seem to work in Rails.

Dan,

Is sys/proctable a gem that I can install? …if so, do you have link?

gem install sys-proctable

Or, you can grab the source at
http://www.rubyforge.org/projects/sysutils

Regards,

Dan

10

jackster the jackle wrote:

thanks

jackster

You haven’t specified what operating system you’re using. On Linux,
the “ps” command generates fields separated by whitespace, so some
simple regex operations will work on them. Other “Unix-like” operating
systems will not necessarily behave this way.

11

On Dec 13, 2007, at 6:52 PM, jackster the jackle wrote:

<%= processes %>
assignments or even return command.
While using 

 elements to preserve whitespace is simple it also

is not entirely consistent.

Remember you are dealing with different user-agents (browsers) on

different platforms.

Particularly, tab characters (that may be generated by some command-

line tool output) may be displayed at different widths depending on

the user-agent and/or the system.

the 
 element is a useful one but its implementations will not be

as predictable for rendering by the user-agent as going back and

breaking that output into some parts to populate some kind of table

or div structure.

Some tools do not produce \n endings even, just relying on terminal
window for line-wrapping…

12

On Dec 14, 9:41 pm, “M. Edward (Ed) Borasky” [email protected]
wrote:

You haven’t specified what operating system you’re using. On Linux,
the “ps” command generates fields separated by whitespace, so some
simple regex operations will work on them. Other “Unix-like” operating
systems will not necessarily behave this way.

This is why you should use sys-proctable. :slight_smile:

Regards,

Dan

13

Thanks for all the help everyone. Someone from the rails forum gave me
what seems like the simplest solution…here’s what he wrote:

The problem you have is an HTML one, not a ruby one.

Basically, HTML ignores a \n unless it is inside a
tag.

So, you can do this instead:

<%= processes %>

And it should work fine.

Also your Ruby code can be just:

def processes
ps -el
end

To get the same result. You don’t need all that splitting or
assignments or even return command.

thanks again for all the good ideas.

jackster