The popen and system mechanisms allow a program to execute another program and in some manner do something with the result, or even manipulate the program while it is running (send input to it).

Write an EXAMPLES section for the popen(3)/system(3) manpage(s) showing the usage of the functions defined in those manpage(s) in a plausible, real-world and if possible only semi-contrived scenario.

All examples should follow the style guidelines in the style(9) manpage.

All examples should be written in a manner that is self-documenting and make copious use of comments in order to explain the actions being taken.

Examples should be real and working code. They should not include headers or even a main function, but it should be reasonable for a developer to copy and paste an example from a manpage and expect it to work.

An example of a manpage with excellent example code is umtx(2).

Deliverables: A complete EXAMPLES manpage section in mdoc format.