POSIX and NI RT Operating Systems

[JordanJMcBain]

I'm pretty enthused about NI Linux and I am just wondering whether or not it supports the POSIX standard (I assume so)?  How does this compare to the version of Pharlap and VxWorks employed by NI?

[Zach J]

@JordanJMcBain,

GNU/Linux is mostly POSIX-compliant.  The Linux kernel supports the Linux Standard Base (LSB), which is mostly-compliant with POSIX and the UNIX standards.  You can find a discussion about the ISO/IES 9945 (POSIX) standard and the LSB that was started back in 2003 at this link. 

Since NI Linux Real-Time utilizes the Linux kernel, and none of the Linux distributions (to my knowledge) are fully-certified as POSIX-compliant, I would say that NI Linux Real-Time is mostly POSIX-compliant as well.  There may be some small cases where POSIX standards do not match up with the Linux kernel, but these will be present in any distribution of GNU/Linux and not just NI Linux Real-Time.

Short answer: mostly!  Let me know if you have any further questions!

Quick Edit:

With regard to your second question, VxWorks and Pharlap ETS are single-mode operating systems that do not allow much interactivity with a target running these operating systems.  You are able to send some commands to the system via a serial connection, but these commands are limited and it is best to think of the systems as a running executable.  They are built with a singular functionality in mind, whereas NI Linux Real-Time is built to allow interaction with the system as well as the applications running on the system.