Hello Tim,
Sure, you could for example issue the following from your C-program to look
for your device DeviceName:
#include <stdlib.h>
...
x = system("grep -c \'^S:.*DeviceName\' /proc/bus/usb/devices");
and check if x >= 1.
I don't know if there are any other methods, there might be, and most likely
there are. No doubt the /proc/bus/usb/devices is created by one.
Best regards,
Edward
----- Original Message -----
From: "Tim Arney" <[EMAIL PROTECTED]>
To: "Edward" <[EMAIL PROTECTED]>
Cc: <[EMAIL PROTECTED]>
Sent: Thursday, November 18, 2004 14:57
Subject: Re: [Linux-usb-users] Detecting unplugged device
> Hi Edward,
>
> Thanks for your quick reply. So can I execute grep from within a C
program? Is
> there no way you know of using the usb library directly?
>
> Cheers,
> Tim
>
> Quoting Edward <[EMAIL PROTECTED]>:
>
> > Hello Tim,
> >
> > My best bet would be to grep the /proc/bus/usb/devices file for your
> > joystick device.
> >
> > HTH
> > Edward
> >
> > ----- Original Message -----
> > From: "Tim Arney" <[EMAIL PROTECTED]>
> > To: <[EMAIL PROTECTED]>
> > Sent: Thursday, November 18, 2004 13:51
> > Subject: [Linux-usb-users] Detecting unplugged device
> >
> >
> > > Hi all,
> > >
> > > I've written a C/C++ program for controlling a robot with a USB
joystick
> > > under linux. For this I'm using the joydev module. Some of our
robots
> > > are quite large and fast, and a safety concern is with the joystick
> > > being unplugged, then the robot should stop. As it stands, when the
> > > joystick is disconnected the "read" call blocks as though there is no
> > > new data. I could open the joystick port as non-blocking, but then
> > > "read" just returns like there's no new data. What I really need to
be
> > > able to do is determine whether the joystick is still attached, and I
> > > figure somewhere along the chain (kernel->usb->input->joystick)
someone
> > > knows whether it's there, and my best guess would be the linux usb
> > > driver. So anyway, I'm essentially looking for a point in the right
> > > direction as to how I might test to see if the joystick is connected
> > > from my C/C++ program?
> > >
> > > If it helps I'm using Debian Sarge with Linux kernel 2.4.26 on an i686
> > > system.
> > >
> > > Thanks a lot,
> > > Tim
> > >
> > >
> > > --
> > > UTS CRICOS Provider Code: 00099F
> > > DISCLAIMER: This email message and any accompanying attachments may
> > contain
> > > confidential information. If you are not the intended recipient, do
not
> > > read, use, disseminate, distribute or copy this message or
attachments.
> > If
> > > you have received this message in error, please notify the sender
> > > immediately and delete this message. Any views expressed in this
message
> > > are those of the individual sender, except where the sender expressly,
and
> > > with authority, states them to be the views the University of
Technology,
> > > Sydney. Before opening any attachments, please check them for viruses
and
> > > defects.
> > >
> > >
> > > -------------------------------------------------------
> > > This SF.Net email is sponsored by: InterSystems CACHE
> > > FREE OODBMS DOWNLOAD - A multidimensional database that combines
> > > robust object and relational technologies, making it a perfect match
> > > for Java, C++,COM, XML, ODBC and JDBC. www.intersystems.com/match8
> > > _______________________________________________
> > > [EMAIL PROTECTED]
> > > To unsubscribe, use the last form field at:
> > > https://lists.sourceforge.net/lists/listinfo/linux-usb-users
> > >
> >
>
>
>
> --
> UTS CRICOS Provider Code: 00099F
> DISCLAIMER: This email message and any accompanying attachments may
contain
> confidential information. If you are not the intended recipient, do not
> read, use, disseminate, distribute or copy this message or attachments.
If
> you have received this message in error, please notify the sender
> immediately and delete this message. Any views expressed in this message
> are those of the individual sender, except where the sender expressly, and
> with authority, states them to be the views the University of Technology,
> Sydney. Before opening any attachments, please check them for viruses and
> defects.
>
-------------------------------------------------------
This SF.Net email is sponsored by: InterSystems CACHE
FREE OODBMS DOWNLOAD - A multidimensional database that combines
robust object and relational technologies, making it a perfect match
for Java, C++,COM, XML, ODBC and JDBC. www.intersystems.com/match8
_______________________________________________
[EMAIL PROTECTED]
To unsubscribe, use the last form field at:
https://lists.sourceforge.net/lists/listinfo/linux-usb-users
