Help: Efficient regular expression

[Robert Dober]

cmd = string[/\s(\S+)$/, 1]
doesnt fetch me anything

No idea that was not my code

program=string.split.last
what if
string = "root 14051 14033 3 08:39 pts/2 00:00:00 /bin/bash -x
-s"
it fetches only -s for me.

As simple as possible, but not simpler. Now we are in the simpler case
But see below

program=string[/[a-z\/]+$/]
the command column mauy start with character. i dont want to limit it in
my regexp. it has to be generic.

with all your comments, i tried
pid = run_process[/\s(\d+)/, 1]
cmd = run_process[/:\d+:\d+\s(\S.*)\s$/, 1]

Does not work the :\d+ stuff might be a parameter of the program

is there any other way?

Yep counting fields after all
x = split
y= x[1]
z = x[7..-1].join(" ")

There might still be a pitfall though in case of some old processes
where you will have to analyse if the date takes one or two fields if
memory serves.

HTH
Robert

 

[Robert Dober]

What is your terminal width, 30?

oops wrong thread, I was caught in the "Beautiful Code Thread".

Sorry
Robert

 

[Robert Klemme]

i mean i need the 2nd column and the last column.

Your regexp isn't too bad. With only a little tweaking I get this
which is not too inefficient IMHO:

irb(main):001:0> s = "root 14051 14033 3 08:39 pts/2 00:00:00 /bin/bash"
=> "root 14051 14033 3 08:39 pts/2 00:00:00 /bin/bash"
irb(main):004:0> s =~
/^\S+\s+(\d+)\s+\d+\s+\d+\s+\d+:\d+\s+\S+\s+\d+:\d+:\d+\s+(\S+)/
=> 0
irb(main):005:0> [$1, $2]
=> ["14051", "/bin/bash"]

Or you can do

irb(main):007:0> s =~ /^\S+\s+(\d+)\s+(?:\S+\s+){5}(\S+)/
=> 0
irb(main):008:0> [$1, $2]
=> ["14051", "/bin/bash"]
irb(main):011:0> /^\S+\s+(\d+)\s+(?:\S+\s+){5}(\S+)/.match(s)[1..-1]
=> ["14051", "/bin/bash"]

Kind regards

robert

 

[Paolo Negri]

You can process the ps output using other commands.

ps -aef|tr -s ' '|cut -d ' ' -f2,8-

This will just print your second column the 8th and anything that
comes after. At this point your regexp only need to split the string
at the first space.

Paolo

 

[Martin DeMello]

You can process the ps output using other commands.

ps -aef|tr -s ' '|cut -d ' ' -f2,8-

This will just print your second column the 8th and anything that
comes after. At this point your regexp only need to split the string
at the first space.

You're in trouble if any of your fields have spaces, though the
specific case of ps -aef looks safe enough.

martin