Learn Linux Shell Scripting - Fundamentals of Bash 4.4

Parameter substitutions – recap

While it probably isn't necessary at this point for you, we'd like to quickly recap parameter substitutions so that we can place it within the greater context of parameter expansion.

As we stated in the introduction, and as you've seen throughout this book, parameter substitution is nothing more than replacing a variable with its value at runtime. On the command line, this looks a little like the following:

reader@ubuntu:~/scripts/chapter_16$ export word=Scriptreader@ubuntu:~/scripts/chapter_16$ echo ${word}Scriptreader@ubuntu:~/scripts/chapter_16$ echo "You're reading: Learn Linux Shell ${word}ing"You're reading: Learn Linux Shell Scriptingreader@ubuntu:~/scripts/chapter_16$ echo "You're reading: Learn Linux ...