I have an HP OfficeJet Pro 8610, and a nixos host.
I can easily set up the printer in cups, using hplip and a hp:/net/... address.
But how can I set up scanning with simple-scan? It doesn't recognize the existence of the printer, neither does sane-find-scanner or scanimage -L.
I have tried running hp-setup, but that fails complaining of error: No module named enum. I have tried installing python27Packages.enum in my user environment and also in the system environment, but no dice.
Thanks,
The problem was that the nix derivation was missing a dependency; specifically on the enum package in python. Luckily, somebody else already spotted and fixed this here; one just needs to update one's nix channel to pick it up.
To use scanning in general in NixOS with an OfficeJet Pro 8610, see here.
Related
I'm trying to compile some raku code I saw on https://replit.com/languages/raku. The code is from Why is Raku reporting "two terms in a row" when I define a new operator?.
It begins like this:
unit module Format;
use List::Util;
...
It fails to compile with:
raku ./main.raku
===SORRY!=== Error while compiling /home/runner/l4gp3hvdnhd/./main.raku
Could not find List::Util in:
inst#/home/runner/.raku
inst#/opt/rakudo-pkg/share/perl6/site
inst#/opt/rakudo-pkg/share/perl6/vendor
inst#/opt/rakudo-pkg/share/perl6/core
ap#
nqp#
perl5#
at /home/runner/l4gp3hvdnhd/./main.raku:3
exit status 1
On the other hand I see this is a valid module - https://raku.land/zef:lizmat/List::Util.
Why is it failing?
TL;DR Run zef install --/test List::Util in the console, put use lib '.'; at the top of your Raku main.raku, and run, don't walk, with your program, before gremlins gleefully render your efforts in vain. Or maybe just listen to Liz and Rawley.
As Liz and Rawley have noted, you need List::Util installed.
But while I largely agree with them in practice (it may be a pain to use replit to do what you're trying to do) I think a different response to complement theirs might be helpful.
One of the ways replit is trying to distinguish itself from other online evaluators, is that it is trying to be akin to a full dev environment.
In reality it's early days in their ambitious project, and beggars can't be choosers (if you're not paying, it's hard to complain if things don't work out as you might want), but of particular relevance for this SO it is worth noting that it does have console/shell facilities and they've installed Rakudo Star, or perhaps just something like it, including the Raku package manager pretty much everyone uses (zef).
Thus this command, which I just ran in replit's console of a new raku session, worked:
zef install --/test List::Util;
(The --/test tells zef not to run tests. I've only got a free account and it looked like replit killed zef's process when I ran just zef install List::Util during its running of tests. Presumably they take too long, but I don't know.)
And then this main.raku also worked:
use lib '.'; # Tell Raku(do) libs are in current directory.
use List::Util <notall>; # Load and import `notall` from module.
say notall { 42 }, 99; # Try it.
But now the rub. As I was composing this answer, the expected happened. My internet connection momentarily flaked out, the replit rebooted the session, and while my main.raku code was rescued, both List::Util and my console history had disappeared, so I had to paste the install command again and rerun it to get the module installed again.
It's all just throwaway container magic, and there's only so much replit has done thus far to make the simulation of a real full local dev environment really work.
Maybe if your Internet connection is rock solid and/or you're using a paid replit account and/or it's the full moon, it'll all work out. Or maybe you're best off following Rawley's advice.
Speaking of which (I mean Rawley's advice to set up your Raku dev environment locally), if you do install locally you can also install the awesome free version of CommaIDE.
You do not have List::Util installed. Since you're using an online interpreter you will most likely have a lot of trouble doing this. Instead I recommend installing Raku on your local machine with rakubrew.
Then run the following commands:
rakubrew build # Make sure to follow the instructions at the end
rakubrew build-zef
zef install List::Util
Now you should be able to run your code on your local machine, and you'll have access to the List::Util library.
I'm new to Elm. and I'm not good at English. So, if any ambiguous or wrong thing is there, please let me correct it.
----------- edit -----------
All my problem below is on WSL. when I'm trying on windows, all work fine. then... why elm install doesn't work on WSL? did you have any idea?
-------- problem --------
when I try to elm-test init, it doesn't work like below
$ elm-test init
Here is my plan:
Add:
elm/random 1.0.0
elm-explorations/test 1.2.2
Would you like me to update your elm.json accordingly? [Y/n]:
-- PROBLEM DOWNLOADING PACKAGE -------------------------------------------------
I was trying to download the source code for elm/random 1.0.0, so I tried to
fetch:
https://github.com/elm/random/zipball/1.0.0/
But my HTTP library is giving me the following error message:
ConnectionTimeout
Are you somewhere with a slow internet connection? Or no internet? Does the link
I am trying to fetch work in your browser? Maybe the site is down? Does your
internet connection have a firewall that blocks certain domains? It is usually
something like that!
but my Browser(Chrome) is working beautifully, and even in WSL (the environment that I run elm-test init command at) is too.
$ curl https://github.com/elm/random/zipball/1.0.0/
https://codeload.github.com/elm/random/legacy.zip/1.0.0<body>You are being redirected.</body></html>
then I also try again to redirect the URL
$ curl https://codeload.github.com/elm/random/legacy.zip
Warning: Binary output can mess up your terminal. Use "--output -" to tell
Warning: curl to output it to your terminal anyway, or consider "--output
Warning: <FILE>" to save to a file.
I think there's no Network Problem. My PC can connect with the repo, and I think it will be downloaded well.
I lastly tried just elm install, and that throws the same error too. it seems like Elm can't connect with the repo, even if My PC can.
$ elm install elm/random
Here is my plan:
Add:
elm/random 1.0.0
Would you like me to update your elm.json accordingly? [Y/n]:
-- PROBLEM DOWNLOADING PACKAGE -------------------------------------------------
I was trying to download the source code for elm/random 1.0.0, so I tried to
fetch:
https://github.com/elm/random/zipball/1.0.0/
But my HTTP library is giving me the following error message:
ConnectionTimeout
Are you somewhere with a slow internet connection? Or no internet? Does the link
I am trying to fetch work in your browser? Maybe the site is down? Does your
internet connection have a firewall that blocks certain domains? It is usually
something like that!
Please help me, what should I do?
I recently had reason to use WSL for elm development. It wasn't much fun and I'm glad to be back on Mac! What I found was that certain disk operations on WSL seemed to go very slowly and that could lead a variety of weird issues.
I was using Webstorm, which does not handle WSL well, so in the end I did everything on C: drive (rather than in /home/...) so that webstorm could run the windows version of elm-format, while my node development environment was run on the linux layer.
That's not a precise answer to your question but just to say that it can be done, but its not an ideal way to write Elm code in my experience
I had same issue and it was solved.
It was due to DNS server settings.
Create a file /etc/resolv.conf and write the following line.
nameserver 8.8.8.8
Then WSL will refer to Google Public DNS and works fine.
However, when restart WSL, the settings revert back.
Therefore, the following settings are also required.
Create a file /etc/wsl.conf and write the following line.
[network]
generateResolvConf = false
wsl --shutdown and restart WSL.
Reference link
https://github.com/microsoft/WSL/issues/4285#issuecomment-522201021
I am currently using the linux-x86.img which I downloaded from the documentation page for gem5 (http://www.m5sim.org/Download), but since I was not able to compile the fscanf and fopen commands on this image I was wondering if there is a more recent image which I could download and use instead.
The error message throw when trying to compile the lines with fopen and fscanf are
./obj/edgelist.o: In function loadEdgeArray': edgelist.c:(.text+0x148): undefined reference to __isoc99_fscanf'
./obj/edgelist.o: In function loadEdgeArrayInfo': edgelist.c:(.text+0x20c): undefined reference to __isoc99_fscanf'
collect2: ld returned 1 exit status
make: *** [test] Error 1
This error is thrown when trying to compile from both from qemu as well as gem5.
Here's one setup that generates such an image with Buildroot. I'm a fan of Buildroot because it builds everything from source. I don't understand how fscanf and fopen could fail in that image, but I have tested them in the above setup and they work fine.
Boot used to work in the past, but gem5 X86 full system boot has been broken for likely easy to fix reasons for a few months now as of March 2020 on the gem5 side, although there are efforts in place to fix it, and so likely it will work again soon: https://www.gem5.org/project/2020/03/09/boot-tests.html
Other alternatives include:
https://gem5art.readthedocs.io/en/latest/ which Jason has been pushing and uses Packer to generate disk images
You can also extract working disk images from Docker: https://hub.docker.com/_/ubuntu This requires exporting them to a file to give to gem5.
It is also worth noting that when the gem5.org website migrated from the old Wiki to the new static website setup in Q1 2020, we lost the ability of doing directory listing under http://dist.gem5.org/dist/current/arm/ for some reason, and so devs were forced to list them one by one on the static website... https://www.gem5.org/documentation/general_docs/fullsystem/guest_binaries
I am not sure why the error is no longer occurring for me, but documenting the steps I went through which might have fixed something. I reinstalled Ubuntu18.04 therefore had to rebuild gem5 and I used the parsec image (http://www.cs.utexas.edu/~parsec_m5/x86root-parsec.img.bz2) referenced in this answer Booting gem5 X86 Ubuntu Full System Simulation
i am newbie to linux kernel and all, is there any way to check the entry points of linux kernel drivers from command line? say for leds-lp5523?
i have seen this document says we can run some sample LED patterns by running the echo commands by running
cd /sys/class/leds/lp5523:channel2/device echo "load" > engine3_mode echo "9d80400004ff05ff437f0000" > engine3_load echo "111111111" > engine3_leds echo "run" > engine3_mode
But i cant find this /sys/class/leds/lp5523:channel2/device directory in my Ubuntu x86-64 PC.
Can anyone help me on this.
Thanks in advance..
This file will not be created until you actually have an LP5523 connected. I doubt this is the case on your PC as this is an i2c chip.
Else, you found the correct documentation. You can usually find two different interfaces for drivers, either device files (usually found in /dev) that are using the usually syscalls (open, read, write, ioctl) or a sysfs interface (found in /sys), the documentation is then found in Documentation/ABI/.
The best way to find whch interface the driver is using is still to read the source code for that driver.
Since it took me quite some time to figure out how to get Xtion (Primesense) to work on VMware I thought to share it here with you. (with Kinect I have a problem to let ROS see the device even though VMware has successfully connected it).
roslaunch openni2_launch openni2.launch
Running the above command gave me the error:
Warning: USB events thread - failed to set priority. This might cause loss of data...
I either got a single frame or no frame when running "rviz" and Add --> Image --> Image topic --> /camera/rgb/image_raw
So how do I get video frames in Ubuntu from a Primesense device while using a Virtual Machine (VMware)?
My specs
Windows 7 running VMware 10.0.4 build-2249910
Ubuntu 12.04.5 Precise in VMware
ROS Hydro
The following question pointed me in the right direction: http://answers.ros.org/question/77651/asus-xtion-on-usb-30-ros-hydro-ubuntu-1210/?answer=143206#post-id-143206
In the answer of blizzardroi (not selected answer) he/she mentions that USBInterface should be 0. I reasoned that since my main Machine is Windows, I should set UsbInterface to 1, which indeed solved it.
Solution
Go to /etc/openni2/ (from system folder, not Home) and open PS1080.ini with administrator rights (e.g. sudo gedit PS1080.ini). Search for UsbInterface, remove the ; and change the value to 1. It should look like below:
; USB interface to be used. 0 - FW Default, 1 - ISO endpoints (default on Windows), 2 - BULK endpoints (default on Linux/Mac/Android machines)
UsbInterface=1
Additional
From previous experience it may also be related that your Windows system may need the kinect drivers as well. If the above not works, try to install the following:
(Kinect SDK) https://www.microsoft.com/en-us/download/details.aspx?id=34808
(OpenNI2 Windows) http://structure.io/openni
p.s. Don't forget your drivers for Ubuntu (replace hydro with your ROS version)
sudo apt-get install ros-hydro-openni*
Important
It doesn't solve the error below, but rviz returns video, which means that we can read the data the Primesense device publishes!
Warning: USB events thread - failed to set priority. This might cause loss of data...
Got the same warning from opennni (issued at start by a binary located at Tools/PSLinkConsole) with another sensor.
Solved by starting process as sudo - my guess: to set priority to USB event threads you need root access. :)