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Variables and math in Bourne Shell

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http://ubuntuforums.org – Hey everybody, I've been searching google and these forums and have found some solutions to the issues I've been having today within the Bourne Shell. I am following chapter 6 of the Guide to Unix using Linux 4th Edition. I am working on some basic calculations with variables in the BASH SHELL and doing the same within the Bourne Shell with modifications. In BASH, I did the following: let X=10+2*7 Type echo $X and press Enter. You see 24 on the screen. Now I realize that the bourne shell does NOT have LET as a command, and I need to use expr. I was able to get the math to wor (Hardware)

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Submitted by dayu on 07/25/2012 – Made popular on 07/25/2012

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Hey everybody, I've been searching google and these forums and have found some solutions to the issues I've been having today within the OLD Bourne Shell.

Some BASH Basics 2 years 9 weeks ago

Before we get ahead of ourselves, it would probably be a good idea to go over some BASH basics.Let's start at the beginning, OK? The Bourne Shell was born at AT&T's Bell Laboratories a while back. It was birthed by Steve Bourne, hence the name. The Bourne Again Shell (bash) is a direct descendent of the Bourne Shell (sh). It's very similar to the critter that Mr.

From the book Advanced Programming in the Unix environment:

Linux uses the Bourne-again shell for its default shell.

The command line is a powerful way to interact with a Linux computer. Instead of using the mouse, you just type commands into the shell. (The shell is a blank window where you type in your commands.) So for example, instead of clicking on your file browser, you simply type ls [enter] to display the contents of your working directory.

I have just started learning the fundamentals of Unix and wondering why there are so many shells in a unix like system .

How can I find out whether a script is written in bash or sh?

The first line of the script is not helpful here, since on Linux, bash scripts have this line: #!bin/sh

Actually, there are many distribution where bin/sh is bash (maybe bin/sh is a link to bin/bash in those distributions), and not Bourne Shell.

Hi I need help to find if a sentence contains a word in Bourne Shell (sh), with bash I would do something like my example.

#!/bin/bash INPUT='Lorem ipsum dolor sit amet.'

if [[ "$INPUT" == *dolor* ]] then echo "So true" else echo "Not true" fi

But this does not work with sh and I can't use bash.

//Fredrik

According to wikipedia, the Bourne shell was introduced in 1977 and C shell in 1978, but unix itself dates back to 1969.

If you were using a unix system before 1977, what shell would you have been using?

My /etc/profile code is:

# /etc/profile: system-wide .profile file for the Bourne shell (sh(1)) # and Bourne compatible shells (bash(1), ksh(1), ash(1), ...).

if [ "$PS1" ]; then if [ "$BASH" ] && [ "$BASH" != "/bin/sh" ]; then # The file bash.bashrc already sets the default PS1. # PS1='\h:\w\$ ' if [ -f /etc/bash.bashrc ]; then .