OK, so you need to learn about unix groups. In essence, you need to create a group, say “cape” and then make your userid a member of this group. After that, do the following:
sudo chown root:cape /sys/devices/bone_capemgr.9/slots Now, as a member of the group “cape”, you are permitted to write to /sys/devices/bone_capemgr.9/slots. Regards, John > On Apr 17, 2016, at 11:24 AM, John Baker <[email protected]> wrote: > > I just now discovered the problem requiring sudo to start my python program. > It's related to PyBBIO library code to write to the PWM interface on the BBB. > I am trying to find out if there is a way around this requirement (to run the > code as root) but I may be stuck with it. :-( > > I get a permission denied error related to the capemgr.9 if I don't run my > code as root. > IOError: [Errno 13] Permission denied: '/sys/devices/bone_capmgr.9/slots' > > John > > On 4/17/2016 9:39 AM, Dennis Lee Bieber wrote: >> On Sat, 16 Apr 2016 16:53:16 -0700 (PDT), John Baker >> <[email protected]> <mailto:[email protected]> >> declaimed the >> following: >> >>> Hi Dieter, >>> Still not working. I have a hunch that the problem is with Tkinter but >>> can't tell. I have to run my GUI program SimB.py with the terminal program >>> on the BBB, typing sudo python SimB.py, then it runs happily. >>> >> The key phrase is "GUI program". >> >>> *Here's my crontab in /etc:* >>> @reboot root /usr/bin/python /home/debian/Desktop/SimB.py >>> * * * * * root /usr/bin/python /home/debian/Desktop/SimB.py >>> >> "cron" jobs do not have a console, much less a graphical session >> manager. >> >>> Apr 16 23:37:14 beaglebone /USR/SBIN/CRON[2292]: (CRON) info (No MTA >>> installed, discarding output) >>> >> You do not have local mail transfer agent (SMTPd or equivalent) so >> whatever error trace cron was going to send is being dropped on the floor. >> >>> >>> I can successfully run my program with a keyboard attached to my BBB using >>> sudo python SimB.py, have to use the sudo, otherwise gets a Tkinter error. >>> I just now double-checked and my GUI program SimB.py runs very happily. >>> Cannot run SimB.py thru putty as it gives the Tkinter error. >>> >> putty implies a text console connection -- unless you have an X-server >> running on the computer AND have configured the login via putty to use the >> computer X-server (environment variable for DISPLAY pointing to the >> computer) there is no graphical environment in which to open the GUI >> program. >> >> When using a direct keyboard/mouse and HDMI connection, the BBB is >> running a local X-server and the (automatic) login is running a >> desktop/window manager that connects to that X-server. Not sure why you'd >> need the sudo -- Tkinter should be able to open a window from the account >> that is running the session manager. >> > > > -- > For more options, visit http://beagleboard.org/discuss > <http://beagleboard.org/discuss> > --- > You received this message because you are subscribed to the Google Groups > "BeagleBoard" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected] > <mailto:[email protected]>. > To view this discussion on the web visit > https://groups.google.com/d/msgid/beagleboard/5713D4C9.8090005%40ieee.org > <https://groups.google.com/d/msgid/beagleboard/5713D4C9.8090005%40ieee.org?utm_medium=email&utm_source=footer>. > For more options, visit https://groups.google.com/d/optout > <https://groups.google.com/d/optout>. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/BDB95044-BDE7-478C-B276-15EA5707AE16%40gmail.com. For more options, visit https://groups.google.com/d/optout.
