Re: Yemc can't connect

[Adriaan Pelzer <adriaan-at-trispen.com>]

Hi,

I still can't get Yemc running as a normal user. I chmod'ed all of the
files below, and now it gets stuck at:

    starting EMC MOTION PROGRAM --
freqmod.o...plat/rtlinux_2_2/lib/freqmod.o: create_module:
Operation not permitted.

I still don't understand why it won't run as root either.

If anyone recognise this, I'll be much obliged.

Regards,

Adriaan Pelzer

Ray Wrote:
>>>
Adriaan

Yep!  You are correct!  These are exactly the symptoms reported if you
try
to run the EMC as a common user.  The messages that you got are only the

first level of errors.  When you fix these, others will pop up like
mushrooms in the spring.  The specific set will change a bit depending
on
the linux, rtlinux, and emc versions that you are using.

Hints at the direction of a solution to the problem can be found in the
handbook

www.linuxcnc.org/handbook/faq/faqemcsafe.html

But I'll give you a quick condensation of the page below:

1--  Fred says

Easy way is to set up a normal Linux user account, say "ray", with a
home
directory, say /home/ray.

Ray won't be able to run the EMC for three reasons:
a. it requires running the /sbin/insmod, /sbin/rmmod, and /sbin/lsmod
programs to install/remove/list the EMC motion controller;
b. it requires accessing /dev/mem to use the shared memory interface;
c. it requires running privileged inb/outb instructions for the parallel
port
IO.

You can get around the first problem by changing the permissions on
/sbin/insmod and /sbin/rmmod so that they are "setuid root". This means
that they run as if root is running them. Set this up, as root, by
doing:
chmod u+s /sbin/insmod /sbin/rmmod /sbin/lsmod

2-- Fred says
You can do the same sort of thing with /dev/mem, by making it read-write

for everyone. As root, do:
chmod a+rw /dev/mem


3-- Will says
You need to (for rtlinux 2+)
chmod a+rw /dev/mbuff


4-- Fred says
You can change the permission on emc/plat/<whatever>/bin/bridgeportio so

that it runs setuid root also. As root, do:
chmod u+s /usr/local/nist/emc/plat/<whatever>/bin/bridgeportio

Ray says, "Here I also change ??task, emcsh, iosh, because I had some
problems with tuning and saving the ?.ini file when the EMC shuts down.
And when I try to watch or change parport bits.

Fred says "To do this, do (as root):

root> chown root emc/plat/linux_2_2_14/bin/iosh
root> chmod u+s emc/plat/linux_2_2_14/bin/iosh

-5- Ray says
The last message that I got when I tried to start the new version was:
running EMC DISPLAY PROGRAM -- tkemc...
Error in startup script: /bin/ls: tcl/scripts: Permission denied
 while executing "exec /bin/ls $scriptdir"
 (file "plat/linux_2_2_14/bin/tkemc" line 570)
To fix this I ran the following command as root.
root> chmod u+s /bin/ls

This is only needed if you run tkemc and/or the various scripts under
that
menu item.

And that should get the EMC going as a user.  Please keep track of your
progress with this and report back so that we can add it to the faq
page.

Thanks in advance.  Hope this helps

Ray
>>>