BASH Shell

How to append text to a file when using sudo command on Linux or Unix

May 30, 2017May 30, 2017in BASH Shell, Linux, UNIX last updated May 30, 2017

I am trying to add entry to /etc/hosts file using ‘sudo echo '192.168.1.254 router' >> /etc/hosts‘ but getting an error that read as, -bash: /etc/hosts: Permission denied. How do I insert or append text to a file when running sudo command on Linux or Unix-like system?

How to count total number of word occurrences using grep on Linux or Unix

May 29, 2017in BASH Shell, CentOS, Debian / Ubuntu, FreeBSD, Linux, RedHat and Friends, Suse, UNIX last updated May 29, 2017

I want to find out how many times a word (say foo or an IP address) occurs in a text file using the grep command on Linux or Unix-like system?

How to use the cURL command to do a POST data to fields on Linux or Unix

May 28, 2017May 28, 2017in BASH Shell, CentOS, Debian / Ubuntu, FreeBSD, Linux, RedHat and Friends, Suse, UNIX last updated May 28, 2017

How do I use the cURL command on Linux or Unix to post data i.e. upload something on Linux or Unix? How do I make a POST request with the cURL Linux command-line to upload file?

How to unzip a zip file using the Linux and Unix bash shell terminal

May 26, 2017May 26, 2017in BASH Shell, Debian / Ubuntu, FreeBSD, Linux, RedHat and Friends, Suse, UNIX last updated May 26, 2017

I grabbed a master.zip file from the Github public repo on my Linux VPS hosted at AWS. How do I unzip the file using bash ssh terminal? How can I unzip a file on Ubuntu/CentOS/Debian Linux/UNIX-like server?

Delete a non-empty directory when you get directory not empty error on Linux

May 24, 2017in BASH Shell, CentOS, Debian / Ubuntu, Linux, RedHat and Friends, Suse last updated May 24, 2017

I am trying to remove a directory named data in my $HOME. However, I am getting an error that read as ‘rmdir: data/: Directory not empty‘. How do I delete a non-empty directory in bash terminal running on Linux operating system?

How to use sed to find and replace text in files in Linux / Unix shell

May 24, 2017May 24, 2017in BASH Shell, CentOS, Debian / Ubuntu, FreeBSD, KSH Shell, Linux, RedHat and Friends, Suse, UNIX last updated May 24, 2017

I am a new Linux user. I wanted to find the text called “foo” and replaced to “bar” in the file named “hosts.txt.” How do I use the sed command to find and replace on Linux or UNIX-like system?

How to ping and test for a specific port from Linux or Unix command line

May 23, 2017May 24, 2017in BASH Shell, CentOS, Debian / Ubuntu, FreeBSD, Linux, RedHat and Friends, Suse, Ubuntu Linux, UNIX last updated May 24, 2017

I wanted to see if a specific port of a desktop computer or server is open from a Linux or Unix command line shell. How do I ping a specific port? Is it possible possible to ping an 192.168.1.254:80 or 192.168.1.254:23 ports?

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