Category Archives: operating system

What is the difference between ls -a and ls -A ?

commandline session $who jeffrin tty7 2014-03-30 00:04 (:0) jeffrin pts/0 2014-03-30 00:06 (:0) $’who’ jeffrin tty7 2014-03-30 00:04 (:0) jeffrin pts/0 2014-03-30 00:06 (:0) $`who` bash: jeffrin: command not found $ls -a > a.txt $ls -A > A.txt $diff a.txt A.txt 1,2d0 < . A.txt $cmp a.txt A.txt a.txt A.txt differ: byte 1, line 1 …

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How to know the command or function for a particular task ?

commandline session $man -k sort alphasort (3) – scan a directory for matching entries apt-sortpkgs (1) – Utility to sort package index files bsearch (3) – binary search of a sorted array bunzip2 (1) – a block-sorting file compressor, v1.0.6 bzip2 (1) – a block-sorting file compressor, v1.0.6 comm (1) – compare two sorted files …

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ssh-keygen — authentication key generation, management and conversion

ahiliation@pluto:~$ ssh-keygen Generating public/private rsa key pair. Enter file in which to save the key (/home/ahiliation/.ssh/id_rsa): Created directory ‘/home/ahiliation/.ssh’. Enter passphrase (empty for no passphrase): Enter same passphrase again: Your identification has been saved in /home/ahiliation/.ssh/id_rsa. Your public key has been saved in /home/ahiliation/.ssh/id_rsa.pub. The key fingerprint is: 70:7f:99:30:63:19:1e:ea:0f:af:ce:7d:dd:e5:55:9a ahiliation@pluto.infoclub.in The key’s randomart image is: …

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WSU pTop is a simple and effcient process-level power profiling tool

$ls conf doc makefile objects.mk sources.mk src $make all cc -c -o src/avltree.o src/avltree.c In file included from src/avltree.c:12:0: src/eperf.h: In function ‘sys_perf_event_open’: src/eperf.h:32:17: error: ‘__NR_perf_counter_open’ undeclared (first use in this function) return syscall(__NR_perf_counter_open, attr, pid, cpu, group_fd, flags); ^ src/eperf.h:32:17: note: each undeclared identifier is reported only once for each function it appears in …

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script — make typescript of terminal session

STITCHED (C) FROM : Virtual Terminals commandline session $script Script started, file is typescript $ls Algorithms bookmark config-files firewall kernel_start.asm loader scripts animation books debian GD kernel_start.s Mail test art.text bugs-general debian-howtos jeffrin language ovlfose typescript beautifulwork cairo Docs kernel linux README web.application $ls -a . beautifulwork config-files GD kernel_start.s ovlfose web.application .. bookmark debian …

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parameter panic – the number of seconds the kernel waits before rebooting on a panic

GNU/Linux PARAMETER root>cat /proc/sys/kernel/panic 0 root>echo 60 > /proc/sys/kernel/panic root>cat /proc/sys/kernel/panic 60 root> PARAMETER EXPLANATION http://en.wikipedia.org/wiki/Kernel_panic PARAMETER FUNCTION panic: The value in this file represents the number of seconds the kernel waits before rebooting on a panic. When you use the software watchdog, the recommended setting is 60. PARAMETER CODE CONNECTION http://lxr.linux.no/linux+v3.12.5/kernel/panic.c

What is nmi_watchdog related to Linux ?

ABOUT NMI Short for non-maskable interrupt, NMI is the highest priority interrupt capable of interrupting all software and non-vital hardware devices. The NMI is not commonly used and usually only used to verify if a serious error has occurred or stop all operations because of a failure. For example, when you press Ctrl+Alt+Del when the …

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