Re: Find argument passed to running process
Re: Find argument passed to running process
- Subject: Re: Find argument passed to running process
- From: Nico Schmidt <email@hidden>
- Date: Wed, 2 Sep 2009 11:37:55 +0200
On 02.09.2009, at 10:07, Terry Lambert wrote:
On Sep 1, 2009, at 9:38 PM, Stephen J. Butler wrote:
On Tue, Sep 1, 2009 at 9:55 AM, Rakesh Singhal<email@hidden
> wrote:
I can find pid for any running process using code given here
http://developer.apple.com/mac/library/qa/qa2001/qa1123.html. But
I want to
find the arguments passed to this running process, when it was
launched. I
checked the kinfo_proc structure but I could not find any thing
related to
arguments.
To actually answer the question, look at the source code for "ps":
<http://www.opensource.apple.com/source/adv_cmds/adv_cmds-119/ps.tproj/ps.c
>
It calls sysctl with { CTL_KERN, KERN_PROC, what, flags } (look a
little higher up for what gets stuffed in those vars). From the
result, it then looks at "kp[i]->kp_proc->p_comm" (saveuser
function).
<http://developer.apple.com/mac/library/qa/qa2001/qa1123.html>
"The UNIX Programming FAQ lists a number of alternative ways to do
this.
Of these, the only approach that works on Mac OS X is exec'ing the ps
command line tool. exec'ing ps will require parsing the tool's output
and will not use system resources as efficiently as Listing 1."
...on the other hand, the ps method is more likely to continue to
work in future versions of the OS. Also note that qa is 7 or 8
years old, based on how you read the dates.
The problem with parsing the output of ps is that it only works with
the most harmless arguments.
If a command line argument contains funny characters like a line feed
for example it will show up as "^M" in ps's output.
I always wondered why there is no way to get the information ps
delivers in a library function. Parsing output may have worked
in the days where a Unix user would not even imagine putting anything
but printable non-whitespace characters in a file name.
Nico
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Darwin-dev mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden