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C Programming Language
=======================

K&R Notes (unstructured)
-----------------------------

With pointer arithmatic, the type of ``foo *p`` is taken into account
automagically. Eg, ``p+3`` -> ``0xFEFE0000 + 3 * (sizeof foo)``.

Examples of tricky pointer sytax::

    int *ip;  
    (++*p)
    (*p++)
    ++(*p)
    *(++p)

In the context of references like function declarations, only the size of the
first dimension of a multi-dimensional array is free; the others must be
specified explicitly::

    void copy_2d_array(int a[][10], int b[][10]); // Ok
    void copy_2d_array(int a[][],   int b[][]);   // Invalid
    void copy_2d_array(int a[10][], int b[10][]); // Invalid

Negative indexing of arrays is "allowed" (reads ahead of the array in memory);
need to check for that case explicitly.

``_FORTIFY_SOURCE`` does what it says. 

In C99 can ``int* p`` replace ``int *p``? Seems like yes. 

The "update statement" of a for loop gets executed at the /end/ of every loop,
which means an iteration variable gets updated once more than might be
expected::

    int i;
    for(i = 0; i < 10; i++) { 
        } 
    printf("%d\n", i); // prints 10, not 9

Any 'inline' should probably be 'static' (local linkage). 

Other References
------------------

"Spiral Rule" trick for understanding type/pointer definitions:
<http://c-faq.com/decl/spiral.anderson.html>

"The Lost Art of C Structure Packing": <http://www.catb.org/esr/structure-packing/>

Notable C Libraries
---------------------

[yajl](https://github.com/lloyd/yajl) ("Yet Another JSON Library"): portable,
incremental, simple, error messages. 

Zed Shaw Notes
----------------

 * cachegrind/callgrind: <http://c.learncodethehardway.org/book/ex41.html>
 * bstring ("better string"): <http://c.learncodethehardway.org/book/ex36.html>
 * testing: <http://c.learncodethehardway.org/book/ex30.html>
 * debug macros: <http://c.learncodethehardway.org/book/ex20.html>

Auto-Indent Styling
---------------------

Via [riolet](https://github.com/riolet/WAFer), this one-liner will auto-indent
files::

    find . \( -name '*.c' -o -name '*.h' \) -exec indent --no-tabs --linux-style --line-length 90 --indent-level 4 -bli0 \{\} \;