Providing parameter defaults

Within bash parameters, there are named spaces in the memory that allow us access to stored values. There are two types of parameters:

  • Variables
  • Special parameters

Special parameters are read-only and are pre-set by the shell. Variables are maintained by ourselves as well as bash. In general, when talking about syntax, bash will refer to variables by their family name of parameters.

Variables

Variables are one type of parameter. These can be set by the system or by ourselves. For example, $USER is a variable parameter that is set by the system but can be written by us. As such, it is not a read-only requisite of special parameters.

Special parameters

Special parameters are the second parameter type and are managed by the ...

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