OT: Interface standards for libraries

[Neal Lippman <nl@lippman.org>]

Are there any sort of standards for library interfaces, and if so, who
decides on them and where are they maintained?

By way of example of what I mean, two examples:

1. I am specing out a program that will work with images, and ideally it
would work with a variety of different image formats, like jpeg, png,
tiff, exif, etc. Now, on my (testing) system, I have libjpeg62, which I
assume is a library of routines for handling jpeg images. So: how would
I go about finding out how to use this library? It would make sense that
a similar interface would exist for libpng as well - is this the case?

2. Suppose I am writing an app that uses sound. Ideally, there would a
"standard" interface for creating sound from an application, that would
link to alsa, oss, whatever sound driver modules were actually in use.
Is this the case, or is my sense that underlying applications in the
Linux/Unix world is simply a smorgasbord of libraries, all incompatible,
so that an appliation cannot simply be written to use "sound" and be
expected to work on any up to date Linux/Unix system - hence the need
for all the dependences and what not that apt handles for us.

nl