postRender system call failure

[project_68]

win7 x64
maya 2011, hf3.
batch rendering in mr

for some reason, when my -postRender script calls the system command and passes the command string, nothing happens.
but when I run the system call in the script editor the system call works just fine.
I've checked my syntax, all conditionals and paths report correctly in the log file.
i'v even tried wrapping the system call in an evalDeferred -lp string....still nothing.

the following is a the relevent section of the postRender script:

    //record render list filename, include in csb_mM2D_compositeContours() function, write in the $cmd as a var, and save as .jsx
            if(!filetest -r $cmdFile)
            {
            string $userScripts = internalVar -uad;
                string $jsPath = ($userScripts + "scripts/csb_tools/scripts/java/csb_mM2D_compositeContours.jsx");

            int $fileID = fopen $cmdFile "w";
                //fprint $fileID ("#target photoshop  \n");
                    fprint $fileID ("#include \"" + $jsPath + "\" \n\n");
                    fprint $fileID ("var cmdPath = new String(\"" + $cmd + "\");\n");
                        fprint $fileID ("csb_mM2D_compositeContours(cmdPath);");
                            fclose $fileID;

            }
            print("running csb_compositeContours() \n");

        //use system to call photoshop, and the .jsx file just written as a parameter
            string $adobePath = ("Photoshop.exe " + $cmdFile);
                evalDeferred -lp ("system(\"start " + $adobePath + "\");");

[joojaa]

Quick comment on the run.

On windows, are you sure photoshop accepts the nonstandard folder notation you using.  Maya does but thats because mayas a quite enlightened cross platform software that was made originally for the unix world. So maya IS a execption to the rule. Most applucations really think folder separation to be a backslash ('\') NOT a shalsh ('/'). No photoshop at hand to verify this.

In any case yous hould probably not use evalDeferred in a batch process with "-lp" even less. You should catch the return of the system statement as any error you do may show up here, tough becase your calling start then the error may go to different subshell. You mayu for testing purposes want to not fork teh running and omit start and eval altogether thisway you can wait for the return. It may be superfuous in the real script.

Second by evaling the string your subjecting yourself to a very hard to detect source for bugs, that admittedly does not  neccesarily affect you here: Beware, you now have one escape more than your variables originally intended! See your strings get parsed down to strings once more which means that escapes escepd for the purpose of typing get exacped once more.

[project_68]

Hi Joojaa, thx for the reply...and for jogging the ole memory!
apparently (while in batch) a system call which uses the keywords "start", "load", or "shell" will not work for me, Im guessing it has something to do with the calling function exiting before the system call can be completed.
a quich read of the MEL ref tells us that the solution is to(as you suggested) wrap the system call in a catch conditional, and call system without a key word eg:

            string $adobePath = ("Photoshop.exe " + (toNativePath ($cmdFile)));
                if(catch(system($adobePath)))
                {
                print("csb_compositeContours() completed sucessfuly \n");

                }
                else
                {
                print("csb_compositeContours() failed! \n");

                }
also, while photoshop extended javaScript does accept (/) or (\) I've used toNativePath for safety in my $adobePath string.
while it worked fine without it in the script editor, if you have taught me one thing its...assume nothing!
all is working great now w/ my -postRender script, I just need to figure out the .jsx method for closing photoshop so my catch conditional will return !=0 and the prosess will exit correctly.....back to the adobe forum:( arggggg.
ps
still waiting for you to write that MEL/API book!
S

[joojaa]

assume nothing!

Well yes, at minimum assume no such thing that you can easily avoid assuming. I mean if it takes you minutes to test and/or avoid all asumptions plese do so. Its easier on you in the future.

But the actual rule of thumb is not to complicate things unnecceserily. The object is to make your work as easy as possible and so avoiding any potenttial ambiguity is just good practice.

PS: I would avoid calling ps with jsx over in maya. Why? Well because its far easier to just use the COM component and the python com api (to get the com api for maya just isntall same version of python as your maya is using standalone and point your maya pythonpath to read the standalone isntals site-packages directory). Then just use teh same calls as the visual basic does but directly in python (with pythons syntax offcourse)

This would benefit you in several ways. 1) you wouldnt need to restart photoshop between runs. 2) you could make meaningfull querries inside your batch script. 3)you could still use jsx from the script. 4) its easier to write.