I just implemented a Linux command shell in python using only the os library’s low level system calls, like fork() and so on. I was wondering how I can implement a key listener that will listen for key (UP|DOWN) to scroll through the history of my shell. I want do do this without using any fancy librari…
VS code not loading Python Interpreter
Here is my VS code infor: My python path is here: But VS codes keeps saying Select Python Interpreter in the status bar even after I selected. But when I try to select, it says it is already being selected. At moment, due to this, I am unable to use Python linter Flake8. When I check the console log. I
transfer rate of dd to a disk is much less than copy file
The case is that I use dd command to build a bootable usb for xxOS. /dev/disk2 is usb device. command is It spends a lot of time, the transfer rate is about 2MB/s~4MB/s. It makes me puzzle, why it’s more slowly than copying files to an USB about 10MB/s or more up. May I use the right parameter? Answer D…
send Ngrok random port number through terminal
I use Ngrok service to forward my local network to the internet but for my specific application as I do not have access to hardware I need to run ngrok automatically after boot and send random port number and host address which ngrok assigns to my local port through sendmail package to a specific email addres…
Meaning of adding 1 on socket file descriptor in select function when using linux socket
What is the meaning of adding 1 on socket file descriptor when using in select function? I create socket file descriptor like below, and use it in select function like below, What is the meaning of +1 in select function? It even does not work when I remove the calculation adding the value. Thanks in advance. …
Find all jvm log files with “Exception” message and list the count of uniq exceptions
I have a list of jvm log files that I need to search for Exception and then list the count of each unique exception . Following is the command I am using: This gives me output of total exception count in each file : How do I modify the command to get the unique exception count? Answer you can use
open command in perl
I am try to use open command in perl. But getting and error as follows. Command open(IN_TRIALS, ‘<‘, “F:/2010_nist_sre_test_set/data/eval/keys/coreext-coreext.trialkey.csv”) or die “cannot open trials list”; Error cannot open trials. how to fix this? Answer First, make s…
How do you create a C program that resembles the nl command in Linux?
I am working on a project to create a C program that acts just like the nl command in Linux, with the exceptions; it only accepts limited options, does not accept dashes to denote standard input, and no need for division of documents into logical pages with headers/footers. This is a link to an nl manual page…
Linux, Installation of FBX SDK, how to automatically confirm?
I am currently building a project in a (Singularity) container, and one of the dependencies is the FBX SDK (for building Qt static). The problem is that the installer of FBX reads the licence conditions and then asks to confirm those, and as the installation by recipe don’t allow me answer manually, it …
Creating a new directory in /dev using udev rule
This is the code snippet responsible for creating the device: My udev rule is the following: From my understanding, this rule should match against the device name given by the kernel module (synchmess) and create the /dev subdirectory “synch”. However, the synchmess device shows under /dev with th…