BASH Shell HowTo - Linux / Unix Q & A from nixCraft

How to add bash auto completion in Ubuntu Linux

last updated November 11, 2018 in BASH Shell, Linux, Package Management, Ubuntu Linux

I set up a new Ubuntu Linux LXD container, but my auto-completion of bash shell commands are not working. How do I enable autocomplete feature in Ubuntu Linux 18.04 LTS?

Bash Shell Find Out If a Variable Is Empty Or Not

last updated August 9, 2018 in BASH Shell, CentOS, Debian / Ubuntu, FreeBSD, Linux, Suse, UNIX

My shell script depends upon user input. How do I find out if a variable called $_JAIL path is empty under a Linux / Apple OS X / Unix like operating systems? Can you tell me command on bash shell to find out if a variable is empty?

Bash Shell Script To Test For Empty Folder

last updated July 6, 2012 in BASH Shell

How do I check if a directory contains files? How do I find out if a directory contains files using bash shell under Linux or Unix like operating systems?

Linux / Unix: Find Hidden Directories, Files and Folders

last updated June 26, 2012 in UNIX

I‘m a new Unix user and trying to find the hidden directory called .movies but I do not know where it is on the file system. How do I find a hidden folder or directories under Unix like operating systems?

Unix / Linux Shell: Parse Text CVS File Separator By Field

last updated March 4, 2014 in BASH Shell, Linux, UNIX

I work for a small ISP (Internet Service Provider) and we are using Linux and Unix-like operating system with bash shell. I want to write a shell script to parse the csv file line by line. Then line must be parse again field by field. The sample input file is as follows:

example.com,username,groupname,homedir,md5password,permission,secondarygroup

I need to extract each of these example.com,username,groupname,homedir,md5password,permission,secondarygroup fields and passed to the different system utilities. How do I write a shell script to automate this task and use the bash shell to parse a text file?

Linux / Unix: Generate A MD5 String

last updated October 4, 2013 in Cryptography, Linux, UNIX

I need to generate a md5 hash for given string. It will be used by shell script to generate keys for remote web service or cryptographic application. How do I generate a md5 hash based on any input string under Linux or Unix like operating systems?

HowTo: Iterate Bash For Loop Variable Range Under Unix / Linux

last updated April 20, 2012 in BASH Shell

How can I iterate bash for loop using a variable range of numbers in Unix or Linux or BSD or Apple OS X operating systems?