Variable Substitution

A variable substitutes a piece of command line.

Description: In DOS a variable is simply a place holder for a piece of command line. At runtime a variable is simply being substituted by its string content. That’s why the string content can be a value, a command, partial value, a partial command or a mix of them. In case of substituting a variable to a command, this command to be substituted can use variables itself. This opens up a lot of space for creativity, e.g.:
  • Handling DOS code as data until execution
  • Creation and execution of temporary DOS code on the fly
See also string manipulation.