05 Apr 09 Simple text sorting

On the command line we have a number of powerful tools available to us. I’m going to cover some text sorting methods here.

I have a file called ‘testfile’ within this file is the following:

test:~# cat testfile
line1
line3
abcdefg

test
line9

this is a test
test file

test
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Tags: awk, cat, grep, sed, sort, text sort, uniq

26 Oct 08 mknod tutorial

mknod is a powerful command with which you can create block or character special files. If you view the man page, you’ll see that you can use it to create block device links and character device links. If you don’t know what these are then don’t worry. The purpose of this tutorial is to explore the FIFO (First In First Out) feature.

A FIFO literally does what it says on the box. The first piece of data to go in is the first piece of data to go out.

The usage of the command is:

Usage: /bin/mknod [OPTION]… NAME TYPE [MAJOR MINOR]

Where MAJOR and MINOR are for the special devices mentioned above.
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Tags: /bin/mknod, beej, block, C, cat, character, device, echo, fifo, first in first out, Linux, major, man, man page, minor, mknod, shell script, special files