sofort: portable software project template

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motivation

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* take care of the elements that are common to all

  (of my) cross-platform C projects, and which, for

  the most part, do not (or at least should not)

  contain any project-specific bits:

  --> the build system;

  --> the argv parser and usage screen generator;

  --> the initial program driver;

  --> and initial front-end utility.

* zero external dependencies: the new project is

  generated from the template project using basic

  shell utilities, specifically cp, grep, and sed.

build system

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* the project is conceived as a library with

  an accompanying front-end utility.

* the configure script is fast and skinny,

  yet comprehensive.

* unified logic for native and cross builds.

* unified logic for in-tree and out-of-tree builds.

driver

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* the provided argv parser and usage screen generator

  is powerful, flexible, and thread-safe; moreover,

  it allows for a program driver that is entirely

  independent of the chosen skin.

skins

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* one benefit of the above design is that it allows the

  front-end utility to have several distinct skins at

  virtually no effort.

modularity

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* the distinct driver and unit context, in combination

  with the thread-safe argv parser, render the front-end

  utility's inclusion in a multi-call binary trivial.

extras

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* the template provides the skeleton of an application

  that may accept one or more files for its input, then

  operate on each input file individually.