[brlcad-devel] Web Interface for BRLCAD

I am creating a web application (using CGI) which act as an interface
between user and BRLCAD. User gives input from browser through HTML
form (inputs like database name, object type, object name etc.) and
ultimately after processing, a shell script is created, which when
executed, a rendered image will displayed back onto browser.

But I stuck with the problem of mged command's non execution in the
shell script. When I run this shell script from browser, mged command
failed to execute (command is correct, tested separately), but when
script run from command line (using Ubuntu, 12.4 LTS), it executed
successfully. I failed to point out, why this is happening?

I experimented by inserting some normal Linux commands like 'ls',
'pwd' etc and by changing user identity to www-data user and then run
script on command line, it run successfully. Now it is strange; since
browser and www-data both are same user, but when script run through
browser it doesn't worked (only mged command fails, all Linux commands
worked and displayed output on browser every time), when from command
line, it worked and .g file created. Only mechanism is different, user
is same, then why via browser script failed?

I further experimented, I redirect script's output to a text file.
Now, every output which was to be displayed onto screen should go to
text file. This thing happened only with Linux commands but not with
those of mged. The output of mged command which marks its successful
execution i.e. name of objects created, appeared on screen but not
directed to standard output i.e. text file. So, one more question is
why the output of mged commands is not redirected to standard output,
but to default output only?

-- 
Harmanpreet Singh