You can use Signposts readily from scripting languages, shell scripts, even within 3rd party apps, with the aid of these tools.
Signposts
A simple command tool to write messages to the unified log in Sierra and later. Now signed, hardened and notarized.
Both are now notarized for added security, there is a small bug fixed in Consolation, and updated documentation.
Survey of changes which have occurred since the first version of the unified log in macOS Sierra, with particular emphasis on Mojave.
Natural language parsing, privacy exploring, update investigating, xattr-tweaking, iCloud poking, log browsing: they’re all here for Mojave.
At last: RouteMap performs some analysis on your Signposts, and with the other tools can be used to estimate latency, and look at macOS system performance too.
Picking the right time system for the purpose is critical when you want to analyse very short periods. Sometimes it takes time to discover how to juggle with time.
Doesn’t writing so much to the unified log result in performance penalties? So how can Apple expect us to use the log and Signposts to measure performance?
Blowhole 7 now writes proper Signposts in Mojave, as well as Pseudo-Signposts in Sierra and High Sierra.
At first I thought it was my mistake. Then it looked like a simple error in the interface. But this bug in Mojave’s signposts is more complex. Here’s a workaround.
The Eclectic Light Company 