awk HowTo - Linux / Unix Q & A from nixCraft

How to print filename with awk on Linux / Unix

last updated November 12, 2019 in BASH Shell, Linux, UNIX

I would like to print filename with awk on Linux / Unix-like system. How do I print filename in BEGIN section of awk? Can I print the name of the current input file using gawk/awk?

Howto: Call Shell Script function In echo statement

last updated January 21, 2011 in BASH Shell

I need to call the function called foo() using echo command in the same statement. How do I all or invoke the function using the echo statement?

Linux: Parse an IP Address

last updated January 28, 2011 in Linux

How do I parse my Linux servers IP address using a Bash shell?

How To Use awk In Bash Scripting

last updated August 7, 2017 in BASH Shell, CentOS, Debian / Ubuntu, FreeBSD, Linux, RedHat and Friends, Suse, UNIX

How do I use awk pattern scanning and processing language under bash scripts? Can you provide a few examples?

Awk Print Line After A Matching /regex/

last updated May 13, 2009 in BASH Shell, CentOS, Debian / Ubuntu, FreeBSD, Linux, RedHat and Friends, Suse, Ubuntu Linux, UNIX

How do I a print line after matching /regex/ using awk under Linux / UNIX operating systems? I’d like print the line immediately after a line that matches /regex/ but not the line that matches itself.

BASH: Prepend A Text / Lines To a File

last updated November 2, 2016 in BASH Shell, CentOS, Debian / Ubuntu, Linux, Linux / UNIX File Formats, Solaris-Unix, UNIX

I am a new Unix system user with a bash as a default shell. I can append text to a file using >> operator but how do I prepend a text to a file? I want the opposite operation of >>? How can I prepend some data to a text file?

HowTo: Read a File Line By Line Using awk

last updated October 1, 2011 in BASH Shell, Debian / Ubuntu, FreeBSD, HP-UX Unix, Linux, OpenBSD, RedHat and Friends, Solaris-Unix, Suse, UNIX

How do I read a file line by line using awk utility under Unix / Linux operating systems?