Unable to open device file /dev/usb/lp0 permission denied

Open function in C says unable to open device: permission denied Ask Question. Asked 6 years, 4 months ago. Active 6 years, 4 months ago. Viewed 2k times. ForceBru Edward Severinsen Edward Severinsen 81 1 1 silver badge 14 14 bronze badges.

First of all you should try running your program with sudo. Add a comment. Active Oldest Votes. Keith Thompson Keith Thompson k 41 41 gold badges silver badges bronze badges. You can use setcap to give more fine-grained permissions than full root access. I had to go to the directory it was in and type sudo.

Post by swulf » Sat Aug 15, am. Post by swulf » Sat Aug 15, pm. Post by bminty » Sat Sep 30, pm. Post by mikb » Sat Sep 30, pm. Post by DennisFaucher » Sat Apr 10, pm. Screen Recorder. Transfer Products. File Management. More Products. Workable Solutions Step-by-step Troubleshooting Fix 1. Use error checking tool An Error Checking Tool is a built-in tool in the Windows system for checking and fixing device errors Full steps Fix 2. Gain permissions to the drive You can access the protected hard drive or USB, files, etc..

Right-click the inaccessible hard drive Full steps Fix 3. Format hard drive First, restore data from an inaccessible hard drive with a powerful data recovery tool.

Then, format Full steps Fix 4. Then, change drive letter and format hard drive Full steps Fix 5. Fix command prompt error The Command Prompt access denied error usually derives from insufficient privilege or write protection Full steps. Was This Page Helpful? I run the software from the PC I had completed tested with the local windows only and it works. Zamani — Absolutely. You need to share the raw printer on the Windows side, then install smbclient and try printing some text files over the network on the Linux side.

Make sure that it all works, then use a WindowsPrintConnector from escpos-php to achieve the same result. THanks so much on the guide and the shared codes. I had check the cmd prompt and the name is user administrator vs mine PC for debugging having its name and its password. I also check the computer name and key in together This is the part where I had edited but still not able to print over the network using the line below and tested one by one. Hi Mike, It took me 2 days to finally complete the debugging!!

Great write-up. Look into the stty command, and see if you can find a device file appearing when you plug in the adapter. I have a question. Nice write up.

I have no problems doing this on the serial port that is also available on the printer. Hello Mike. I am still getting this error in browser even if i followed all guide. In terminal, I can print test characters.

If have solution, please help me thanks. Thank you very much, Mike. I spent days trying to get my Raspberry Pi to talk to a printer. The essential command sudo usermod -a -G lp pi seems to be missing everywhere else.