What is the meaning of "POSIX"?

linux unix posix terminology
claws picture claws · Nov 23, 2009 · Viewed 328.2k times · Source

What is POSIX? I have read the Wikipedia article and I read it every time I encounter the term. The fact is that I never really understood what it is.

Can anyone please explain it to me by explaining "the need for POSIX" too?

Answer

Alex Martelli picture Alex Martelli · Nov 23, 2009

POSIX is a family of standards, specified by the IEEE, to clarify and make uniform the application programming interfaces (and ancillary issues, such as commandline shell utilities) provided by Unix-y operating systems. When you write your programs to rely on POSIX standards, you can be pretty sure to be able to port them easily among a large family of Unix derivatives (including Linux, but not limited to it!); if and when you use some Linux API that's not standardized as part of Posix, you will have a harder time if and when you want to port that program or library to other Unix-y systems (e.g., MacOSX) in the future.

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