[SOLVED] finding problem in opening file /dev/ttyS0

shailendragour50 · 07-20-2011, 02:47 AM

i am working in serial communication program while opening file /dev/ttyS0 i am finding problem plz help me

AndyLandy · 07-20-2011, 04:10 AM

Can you be a little bit more-specific? If you do 'ls /dev/ttyS0', do you even have the relevant device entry?

Are you using a serial port on your PC, or are you using an add-on (PCI card or USB dongle)? Sometimes they are assigned different device names.

shailendragour50 · 07-20-2011, 08:21 AM

Quote:

Originally Posted by AndyLandy

Can you be a little bit more-specific? If you do 'ls /dev/ttyS0', do you even have the relevant device entry?

Are you using a serial port on your PC, or are you using an add-on (PCI card or USB dongle)? Sometimes they are assigned different device names.

Thanks for replay
Yes i am using serial port on my pc ,when i am opening the file " fd = open("/dev/ttyS0", O_RDWR | O_NOCTTY | O_NDELAY);" And debugging it showing following message "opening_error: Permission denied" plz help

AndyLandy · 07-21-2011, 05:07 AM

Obvious question, but do you have permission to access the serial port? You probably need to be root to write to low-level hardware devices.

shailendragour50 · 07-21-2011, 07:03 AM

Its working now .....
Thanks