Shell scripting tutorial
From Linuxintro
Revision as of 00:12, 2 January 2012 by imported>ThorstenStaerk (→conditions)
Hello world
echo "hello world"
#!/bin/bash echo "hello world"
input
echo "what is your name? " read name echo "hello $name"
Note that the variable is called $name, however the correct statement to read it is
read name
It is a common mistake to write
read $name
which means "read a string and store it into the variable whose name is stored in $name"
conditions
echo "what is your name? " read name if [ $name = "Thorsten" ]; then echo "I know you"
line feeds
Let's look at the following script:
read name if [ $name = "Thorsten" ]; then echo "I know you"
Instead of a semicolon you can write a line feed like this:
read name if [ $name = "Thorsten" ] then echo "I know you"
And instead of a line feed you can use a semicolon:
read name; if [ $name = "Thorsten" ]; then echo "I know you"
If you want to insert a line feed where you do not need one, e.g. to make the code better readable, you must prepend it with a backslash:
read \ name if [ $name = "Thorsten" ] then \ echo "I know you"