Archive for the 'Tools' Category

Links 2017-05-15

On tools …

  • Setting the Record Straight: containers vs. Zones vs. Jails vs. VMs
    Solaris Zones, BSD Jails, and VMs are first class concepts. [..] Containers on the other hand are not real things.
  • CPU Utilization is Wrong
    The metric we all use for CPU utilization is deeply misleading, and getting worse every year. What is CPU utilization? How busy your processors are? No, that’s not what it measures. Yes, I’m talking about the “%CPU” metric used everywhere, by everyone.
  • Practical jq
    I really love jq, the JSON processor. It has changed my life and pretty much replaced Perl and Ruby as my ETL and data-munging go-to tools.
  • Reshaping JSON with jq
    Working with data from an art museum API and from the Twitter API, this lesson teaches how to use the command-line utility jq to filter and parse complex JSON files into flat CSV files.
  • A Visual Guide to What’s New in Swagger 3.0
    Over the past few years, Swagger 2 has become the de facto standard for defining or documenting your API. Since then, it’s been moved to the Linux foundation and renamed to OpenAPI Spec.
  • A plan for open source software maintainers
    As I envision it, a solution would look something like a cross between Patreon and Bugzilla: Users would be able sign up to “support” projects of their choosing […] and would be able to open issues.

let’s learn tcpdump

When I worked on IPv6 implementations I used tcpdump(1) on a daily basis. — Those times are long gone, but even today it is an extremely helpful tool. Just last week it helped me to debug a database connection problem.

To quote the great Rachel: “tcpdump -e can resolve a great many mysteries.”

If you never used tcpdump (or Wireshark) before then Julia Evan’s zine “let’s learn tcpdump” is a great place to start and to learn the 3-7 important command line parameters.


My First FreeBSD Port

A nice surprise last week: textproc/libcrm114 became my first official FreeBSD port.  :-)

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LaTeX minted

The minted package is a possible alternative to listing. It provides syntax highlighting for sourc code in LaTeX documents by calling the Python pygmentize tool.
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As the name says CUnit is an xUnit implementation for the C programming language.

In comparison to dynamic programming languages the test organization requires much more manual glue code. Because C has no introspection one has to register every test case manually. Likewise there is no support for utilities like mock object generation or annotations.

On the other hand unit tests can be very useful in C, for example when implementing data structures. Test cases may isolate null pointer dereferencing and one can use valgrind on them to detect memory leaks at the lowest level.

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Ich möchte certutil für Unix haben… Dieses Windows-Tool dekodiert und verarbeitet ASN.1-Dateien für kryptographische Protokolle. Dabei kann es mehr als nur X.509-Zertifikate lesen (das geht auch mit den openssl-Tools gut) – ich brauchte es konkret um mir eine PKCS#7 Signatur anzeigen zu lassen.

(Ein Programm gleichen Namens ist übrigens Teil der Mozilla Network Security Services; aber auch das arbeitet „nur“ mit X.509 Zertifikaten.)