Thursday, October 29, 2015

How to get caller function in Clojure

I posted this question on Clojurians slack channel.
What's clojure equivalent of ruby's `caller` method? http://ruby-doc.org/core-2.2.3/Kernel.html#method-i-caller
To put it another way, if a function is call from multiple places, at runtime, is there a way to print out caller for debugging purpose?
Thanks to Alex Miller. He answered
the Thread class has methods to inspect the stack
(Thread/dumpStack) will just dump that thread's stack to stderr
or (Thread/getStackTrace) gives you an array of StackTraceElement's that you can traverse and do whatever
Basically, we can just use Java's Thread class. To be more precise, getStackTrace is an instance method so we have to call it this way.
(.getStackTrace (Thread/currentThread))
We'll get back Java's array of StackTraceElement class.

You can copy and just use a function I wrote here https://gist.github.com/visibletrap/bdf16dd5596c9a72ec73

Tuesday, October 13, 2015

Convert FLV to MP4 with FFmpeg

Only for no AV recording
$ ffmpeg -i input.flv -c copy -copyts output.mp4
Tested on: OS X 10.11
Credit: http://superuser.com/a/860127

Collectd PostgreSQL Plugin

I couldn't find this link when searching with google https://www.collectd.org/documentation/manpages/collectd.conf.html#plugin-postgresql