C Program to execute programs in same console

usleepless at gmail.com usleepless at gmail.com
Tue Apr 4 21:30:52 UTC 2006


Jon,

i believe you are mixing up some concepts.

1. if i read your title "C Program to execute programs in same
console". i think this is easy, just use system("ls *.txt") and you
are done. i believe you can choose wat to do with the output, i am not
sure.

2. but you come up with the cd-command, which you want to change the
context of your parent shell.  changing the home-dir of the current
process ( your program ) can be done with chdir. altering the context
of your parent-shell-process can not be done, except for setting
environment variables ( through the proper C calls )

but if you are running your program, your "shell" (interpreter) is
temporarily not there:  your program is running the show. every
system,execvp or whatever call will give you a child-process with a
new shell, not the parent-shell-process. i believe you may set
environment variables in your parent shell with the appropiate library
calls, but not through a system/execvp call.

so, maybe you should define what you really want to achieve. for
example, qdvd-author runs alls kinds of external programs to generate
thumbnails and slideshows for example.

anybody please correct me if i am wrong.

regards,

usleep


On 4/4/06, Jonathan Herriott <herriojr at gmail.com> wrote:
> Thanks for the suggestion.  I haven't tried it yet, but I'll post if I
> get it working.
>
> Thanks,
> Jon
>
> On 4/3/06, cpghost <cpghost at cordula.ws> wrote:
> > On Mon, Apr 03, 2006 at 05:45:19PM -0400, Bill Moran wrote:
> > > On Mon, 3 Apr 2006 21:39:11 +0000
> > > "Jonathan Herriott" <herriojr at gmail.com> wrote:
> > > > So, my question is how can I get it to execute a cd in the current
> > > > shell using c code.  You don't have to give me the code, just give me
> > > > a term to search for or a function to look up.  I'm sure someone knows
> > > > how to do it here!
> > >
> > > Unless I'm misunderstanding your question, "man 2 chdir" should help
> out.
> >
> > Hmmm... chdir(2) would not change the parent process' (the shell's
> > process) current working directory, only the current working directory
> > of the process running the C program.
> >
> > Perhaps connecting to the shell via a pty, and then sending it a 'cd'
> > command could work? Of look at how expect(1) (/usr/ports/lang/expect)
> > implements this kind of stuff...
> >
> > Regards,
> > -cpghost.
> >
> > --
> > Cordula's Web. http://www.cordula.ws/
> >
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