I recently contributed to SwiftSyntax, a subproject of the Swift open-source project. Building Swift and its subprojects from scratch and then unit-testing them takes about three hours, and the Terminal command is both long and complicated. A build-and-test run can output more than a megabyte to Terminal. Some of this output is potentially useful for diagnosing build-or-test failures. As an iOS developer, I haven’t spent much time in Terminal, but, in the course of running long and long-running Terminal commands recently, I reacquainted myself with some Unix tricks that I developed in the late 90s while working primarily on AIX, which, like macOS, is a Unix. These tricks could potentially benefit anyone running Terminal commands that are long, that take a long time to complete, or that generate a lot of output.
I took an extended break from the software industry. For one of those years, I was an IT guy. For eight of those years, I was a lawyer. I haven’t hitherto mentioned this period on my blog, one mercenary goal of which is to enhance my iOS-developer brand. But I value the skills I acquired during these years because they remain useful. This post describes two examples.