One thread writes to a file (or even delete it), another one calls sendfile() for that file simultaneously for overlapping positions. What is the expected behaviour here? Also, If my understanding is correct, sendfile call will just add a record to socket (file description, position, length) and return to cal…
grep lines that contain 1 character followed by another character
I’m working on my assignment and I’ve been stuck on this question, and I’ve tried looking for a solution online and my textbook. The question is: List all the lines in the f3.txt file that contain words with a character b not followed by a character e. I’m aware you can do grep -i R…
Can not start docker engine in Oracle Linux
I followed the instructions in this blog “https://blogs.oracle.com/hlsu/install-docker-on-oracle-linux-7” to install docker engine in my Oracle Linux 7 server. This is my log for yum install docker-engine : it seems to have installed correctly but the next step i,e. to start the docker gives me th…
Recursively re-spawn file on fsnotify Remove/Rename (Golang)
The Goal: I am attempting to monitor a file that is subject to being moved or deleted at any time. If and when it is, I’d like to re-generate this file so that an app can continue to write to it. Attempted: I have attempted to do this by implementing two functions, monitorFile() to listen for fsnotify e…
Equivalent to named pipes in Unix for LIFO/Stack structure
I have been looking at all the different types of Unix file: regular files, directories, device files, symbolic link, doors, socket, named pipes,… but I couldn’t find a file type that would behave like a stack/LIFO structure. As most of you know, the advantage of FIFO/named pipe over regular files…
SFTP Manual command succeed but script is failing at 1 or 2%
I wrote a script to transfer a folder from VPS to Synology NAS Server. The script fails at 1 or 2% transfer without any indication why. When I run the command manually it works fine without any issues and it transfer the folder flawlessly. I’m not sure what is causing this and would appreciate if i can …
How do I run Perl’s “prove“ TAP harness in unbuffered mode?
As part of a test suite written in Python 3[.4-.6] on Linux, I have to run a number 3rd-party tests. The 3rd-party tests are bash scripts. They are designed to run with Perl’s prove TAP harness. One bash script can contain up to a few thousands of individual tests – and some of them can hang indef…
Send KillAll to multiple node process and wait response
I’m creating a script that makes some pull from a git repository. but first i want to send a SIGUSR1 to multiple nodes that i have running in the machine, and once all the procesess stop i will proceed to git pull so basicly i will run because my node is doing an infinite loop, i want to intercept this
Get filesystem creation date in C
I need to know the creation datetime of the filesystem on a disk (in a Linux machine) with C. I would like to avoid using shell commands, such as and make a parser. Thanks Answer From a program coded in C (or in any language capable of calling C routines) you would use the stat(2) system call (or, with recent
Swapping the first word with itself 3 times only if there are 4 words only using sed
Hi I’m trying to solve a problem only using sed commands and without using pipeline. But I am allowed to pass the result of a sed command to a file or te read from a file. EX: Anyway lets say I had a file F1 and its contents was : The output should be: Explanation: the program must only print