Path: utzoo!attcan!uunet!ctbilbo!ray
From: ray@ctbilbo.UUCP (Ray Ward)
Newsgroups: comp.unix.questions
Subject: Re: Can a parent process determine its child's status ?
Keywords: /proc filesystem
Message-ID: <30@ctbilbo.UUCP>
Date: 2 Mar 90 17:47:20 GMT
Reply-To: ray@ctbilbo.UUCP (Ray Ward)
Organization: Communications Technology Corp
Lines: 38

In article <12229@smoke.BRL.MIL> gwyn@brl.arpa (Doug Gwyn) writes:
>In article <22@ctbilbo.UUCP> ray@ctbilbo.UUCP (Ray Ward) writes:
>-You have pointed out one of the areas that needs improvement for
>-real time applications, among others.  How does one get complete
>-status information on a process, running or not, etc., without
>-awkward programming contortions?  There is no easy way.
>
>Sure there is.  You can access that information through the /proc
>filesystem.  If you don't have this, complain to your vendor.

You are entirely correct about the /proc filesystem.  My thought,
however, was that since the posting was to c.u.questions, and since
the poster was obviously new to the more subtle details of 
handling child processes, a more basic and more generally applicable
response was indicated.

If you have SVR4 UNIX, which was released to the general public
last fall, and have been into the /proc filesystem, and know how
to use ioctl() to extract ps-type information (undocumented in
both the SVR4 Migration Guide and my copy of the SVID89) or how
to extract the information directly from the image of the process
through the /proc filesystem, then you have a way to access
process information directly.   (Of course, with this level of
knowledge, one might be posting answers in c.u.wizards instead
of posting questions about the status of child processes in
c.u.questions...)

I have noticed from your other postings that you are very knowledgeable
as well as helpful.  Have you slipped into one of my habits --
giving a more technical response than is indicated -- or have I
misjudged, on the low side, the technical experience of the poster?
Or, indeed, of c.u.questions?

-- 
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Ray Ward                                          Email:  uunet!ctbilbo!ray  
Voice:  (214) 991-8338x226, (800) 331-7032        Fax  :  (214) 991-8968     
=-=-=-=-  There _are_ simple answers, just no _easy_ ones. -- R.R. -=-=-=-=