How to see the RStudio version you run from the command line?

Just use the RStudio.Version() function:

> RStudio.Version()
$citation
To cite RStudio in publications use:

  Posit team (2025). RStudio: Integrated Development Environment for R. Posit Software, PBC,
  Boston, MA. URL http://www.posit.co/.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {RStudio: Integrated Development Environment for R},
    author = {{Posit team}},
    organization = {Posit Software, PBC},
    address = {Boston, MA},
    year = {2025},
    url = {http://www.posit.co/},
  }

$mode
[1] "desktop"

$version
[1] ‘2025.8.0.356’

$long_version
[1] "2025.08.0+356"

$release_name
[1] "Cucumberleaf Sunflower"