Launching an application from CUPS Backend

[Anonymous]

> Mohit Kumar wrote:
> >
> > Hi All,
> >
> > I am writing a backend for CUPS, which would finally print a pdf file. However, after printing I want to open this application in any PDF Viewer, say Adobe Reader.
> >
> > Is it possible for me to do so?
> >
> > I had tried to "execvp" Adobe Reader with the name of the file as the argument, but nothing happened. So I was wondering if there is something that can be done in this regard or some one has some mechanism to make this working.
> >
> > Any kind of help would be highly appreciated.
> >
> > Thanks,
> > Mohit
>
> You need to launch a process under the id of the user who requested the print operation.
> And, this will only be feasible if the CUPS server and the user's workstation is the
> same machine. If not, you almost certailny will run into trouble with remote execution
> and/or display access rights.
>
> Perhaps you can afford to wait for a stable CUPS 1.2 and then hook to the notification
> mechanism to launch your viewer at the client's side.
>
> Helge
>
> --
> Helge Blischke
> Softwareentwicklung
> SRZ Berlin | Firmengruppe besscom
> http://www.srz.de


Hi Helge and all,

I have been unable to open the application as suggested by you. The following is the code I have written:

for(countParams=0; countParams<3 ;countParams++)
   commandLine[countParams]=NULL;
commandLine[0] = (char*)malloc(20*sizeof(char));
strcpy(commandLine[0],"xpdf");
commandLine[1] = (char*)malloc((strlen(outfile)+1)*sizeof(char));
strcpy(commandLine[1],outfile);
pid = vfork();
if(!pid)
{
	execvp(commandLine[0],commandLine);
	_exit(1);
}

outfile is the name of the file being printed.

What am I doing wring here?

Moreover, are you aware of any API which would let me open the process with the credentials of the user who had requested the print? I have the knowledge of the user who had requested a print.

Any kind of help would be highly appreciable.

Thanks,
Mohit