-rw-r--r--. 1 root root 32 Feb 17 20:32 hello.sh

Basic Commands and Simple Shell Scripts
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We can run the script, obtaining the same output as before:
[root@rhel-instance
]# ./hello.sh
hello world!
To have more clarity, when using the value of the variable, we will put the name of it between curly braces, { and }’, and take this as a good practice.
The previous script will look as follows:
#!/bin/bash
PLACE=''world''
echo 'hello ${PLACE}!''
We now know how to create a basic script, but we may want to have greater control over it by using some programmatic capabilities, starting with loops. Let’s go for it!
for loops
What if we want to run the same command over a list of places That’s what a for loop is used for. It can help iterate over a set of elements, such as a list or a counter, for example.
The for loop syntax is as follows for To specify the iteration do To specify the action done To close the loop
We can define a space-separated list to try it and iterate through it with our first for loop:
#!/bin/bash
PLACES_LIST="Madrid Boston Singapore World"
for PLACE in ${PLACES_LIST}; do echo "hello ${PLACE}!"
done
Let’s run it. The output will look as follows:

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