Very Computer

I would like to get the pid "automatically" by starting a process.

To be more precise: I would like to start a process by means of a script
that (when the process has started) manipulates this process. For this
purpose I need the pid of the just started process.

Is there an easy way without ps and grep? When I start the process
manually in a csh, there appears the pid as the second string. Can I
make use of this output in a script?

Thanks for hints, Thomas

You can get hold of the current PID by examing the variable $$ - I'm not
sure if this helps you or not.

John

eg)
#/bin/sh
echo "Welcome to my script etc....."
echo "The current PID is "$$

Quote:> Hello,

> I would like to get the pid "automatically" by starting a process.

> To be more precise: I would like to start a process by means of a script
> that (when the process has started) manipulates this process. For this
> purpose I need the pid of the just started process.

> Is there an easy way without ps and grep? When I start the process
> manually in a csh, there appears the pid as the second string. Can I
> make use of this output in a script?

> Thanks for hints, Thomas

Quote:> Hello,

> I would like to get the pid "automatically" by starting a process.

> To be more precise: I would like to start a process by means of a script
> that (when the process has started) manipulates this process. For this
> purpose I need the pid of the just started process.

> Is there an easy way without ps and grep? When I start the process
> manually in a csh, there appears the pid as the second string. Can I
> make use of this output in a script?

* Directly from the script from which a process was invoked via:

  - $$ The pid of the current shell invocation
  - $!  The pid of the last launched background command

  So, for example:

  ./myBackgroundJob &
   mBJpid=$!;

   echo "My background job pid is: $mBJpid";

* Via the 'ps' (process status) command:

  ./myBackgroundJob &
   mBJpid==`ps | grep 'myBackgroundJob' | grep -v 'grep' | cut -d' ' -f1`

   echo "My background job pid is: $mBJpid";

The above applies to Bourne (and derived) shells. I don't know what
facilities 'csh' offers in this regard.

I hope this helps.

Quote:>Hello,

>I would like to get the pid "automatically" by starting a process.

>To be more precise: I would like to start a process by means of a script
>that (when the process has started) manipulates this process. For this
>purpose I need the pid of the just started process.

>Is there an easy way without ps and grep? When I start the process
>manually in a csh, there appears the pid as the second string. Can I
>make use of this output in a script?

>Thanks for hints, Thomas

I'va got something for you. I don't know if you're like it but il solves
the problem.
The only thing is that it uses some PERL script. See bellow.

If you replace Thomas_process correctly, it will work fine: you'll get
Thomas_process id in variable ${process_id} and in the else branch.

Is it enough ?

Edouard

#!/usr/local/bin/perl -w

$process_id = fork();
if (${process_id} == 0)
{
#this is the child
    print("Child id $$\n");
    exec(". Thomas_process");

Quote:}

Quote:}

ps does not work as several jobs with the same name exist.

Does someone know the translation to the csh?

#!/bin/bsh
xcalc&
echo $!
kill $!

This example echos the pid of xcalc and than kills xcalc (just an example)

 > $$ and $! work but not in the csh

I bet that's wrong even for your version?  See the manpage about $$ and
$child!  Obiously you missed important things from the manpage, see a
posting named "manpages" in this group for how to ease reading them.

 > X-Mailer: [...] IRIX64 6.5 IP30

Fine in /bin/csh on both 'IRIX 6.5' and 'IRIX64 6.5' (6.5.10f) here.

Sven

#!/bin/bsh
xcalc&
echo $!
kill $!

but this doesn't:

#!/bin/csh
xcalc&
echo $!
kill $!

Probably the syntax is incorrect. Do you know the correct one?

Dankeschoen,

Thomas

 >>> [IRIX]
 >>> $$ and $! work but not in the csh

 >> [...] See the manpage about $$ and $child!

 > #!/bin/csh   [... but with sh syntax]
 > Probably the syntax is incorrect. Do you know the correct one?

I do, after reading csh(1), although i don't use csh.
Why do you insist in not reading the manpage and using the variables
which i even had mentioned above, instead?

Common note:  $child is not portable csh (nor tcsh) syntax, but available
on the mentioned IRIX versions ("IRIX 6.5:1286818620 built 10/11/00
at zebub:/xlv51/6.5.10f/root").

We better ?switch? to email now.

[f'up2p]
Sven, no *csh user