How to print gerber files? (mac)

gerbv - A Free/Open Source Gerber Viewer, part of gplEDA, does what you want. Specifically it is at http://gerbv.geda-project.org/.

gerbv is available for OS X. It can print to PDF or PostScript.

With Homebrew installed, type in your terminal:

brew install gerbv

let it install then type:

gerbv

and it will open