#Linux

What is an EXT4 The ext4 file system is a scalable extension of the ext3 file system. It can support files and file systems up to 16 terabytes in size. It also supports an unlimited number of sub-directories (the ext3 file system only supports up to 32,000), though once the link count exceeds 65,000 it resets to 1 and is no longer increased. Ext4 uses extents (as opposed to the traditional block mapping scheme used by ext2 and ext3), which improves performance when using large files and reduces metadata overhead for large files. [Read More]

Preface grep command syntax redirect output using pipe Regex patterns using -E Preface One of the most useful and versatile commands in a Linux terminal environment is the “grep” command. The name “grep” stands for “global regular expression print”. This means that grep can be used to see if the input it receives matches a specified pattern. This seemingly trivial program is extremely powerful when used correctly. Its ability to sort input based on complex rules makes it a popular link in many command chains. [Read More]

Meltdown is a chip-level security vulnerability that breaks the most fundamental isolation between user programs and the operating system. It allows a program to access the operating system kernel’s and other programs’ private memory areas, and possibly steal sensitive data, such as passwords, crypto-keys and other secrets. spectre-meltdown-checker is a simple shell script to check if your Linux system is vulnerable against the 3 “speculative execution” CVEs (Common Vulnerabilities and Exposures) that were made public early this year. [Read More]

Preface Head basic usage n number of lines Specific number of bytes only Preface There are several commands and programs provided by Linux for viewing the contents of file. Working with files is one of the daunting task, most of the computer users be it newbie, regular user, advanced user, developer, admin, etc performs. Working with files effectively and efficiently is an art. Today, in this article we will be discussing the most popular command called head. [Read More]