Interesting trivia

• index[array] ≡ array[index] ≡  *(array + index)
• arguments to a function may be evaluated in any order by the compiler
• The signed-ness of plain char is compiler-dependent

C99 Hotness

• Boolean type introduced:

#include <stdbool.h>
bool a = true, b = false;

• //-comments formally allowed
• declarations can go anywhere within a function; C89 forces you to declare everything at the start of the function

Syntax

#include <something_in_std_lib.h>
#include "your_own_lib.h"
enum SomeEnum {A, B, C};
typedef someDeclaration newTypeAlias;

• const keyword, like Java’s final
• static keyword means private to this source file, like C#’s internal

Basics

int main(int argc, char * argv[])
char aStringVariable[length];

• EXIT_SUCCESS, EXIT_FAILURE defined in stdlib.h

Function pointers

int foo(char);//declare function
int (*funcPtr)(char) = foo;
int result = funcPtr('a');//use func pointer

Objects

Defining

struct Foo
//unions use same syntax, just w/ different keyword
{
    int a;
    char b;
}

Using

/* C99: */ struct Foo bar = {.b = 'Q', .a = 42};
/* C89: */ struct Foo baz = {42, 'Q'};

Defining macros

• Function-like macros: #define foo(a,b) ((a)-(b))
• The ## operator within macros:
  • Given: #define foo(x) MSG_##x
  • Then: foo(A) ≡ MSG_A
• The # operator within macros – converts operand to string

Useful macros

Assertions:

#include <assert.h>
assert(booleanExpression);

• #define NDEBUG – disables asserts
• #error "Message" – causes compile error with given message
• Conditional compilation: #if, #elif, #else, #endif

Metadata macros

• __func__ – name of current function
• __LINE__ – current line number
• __FILE__ – name of current file
• __TIME__ – time of compilation
• __DATE__ – date of compilation

Standards macros

• __STDC__ – bool for whether compiler is C89-compliant
• __STDC_VERSION__ – 199901L >= if C99-compliant
• __STDC_IEC_559__ – bool for IEEE-754 compliance

Stdlib survey

• stdlib.h: malloc(), free(), array sorting, binary search, str->num conversion, random numbers
• stddef.h: defines NULL, size_t
• string.h: also includes general array/memory stuff
• math.h, time.h: speak for themselves
• errno.h: defines errno global var
• ctype.h: ASCII character classification
• fenv.h: controls floating point rounding mode, etc [C99 only]
• limits.h: limits of integer types
• float.h: describes properties of float representation
• See also my summary of the essential parts of the stdlib

GCC options

• -o exec_name (instead of a.out)
• -Idir_name:other_dir_name (places to also look for headers)
• -fsyntax-only (just check syntax)
• -ansi (use C89)
• -std=c99 (use C99)
• -Wall (warn about a bunch of stuff)
• -pedantic (adhere pedantically to standard)
• -Wextra (warn about strange/pointless code)
• -g (add debug info)
• -pg (add profiling hooks)

• Grab the nearest book.
• Open it to page 56.
• Find the fifth sentence.
• Post the text of the sentence in your blog along with these instructions.
• Don’t dig for your favorite book, the cool book, or the intellectual one: pick the CLOSEST.

Here’s my fairly boring quote from Robert’s Rules of Order Newly Revised – In Brief (which beat out The Definitive ANTLR Reference by mere inches):

If the bylaws are silent on the method of appointing members of special committees, the method is typically set for that committee in the motion creating the committee.

Parliamentary procedure may be dry, but it is truly essential to running good meetings. I got this book just a few weeks ago using overnight shipping to prepare for the first Associated Students Council meeting I attended.

Let’s just hope I never have to move to Object to the Consideration of a Question.

P.S. The naming of the Previous Question motion is just plain confusing, history be damned. Thank goodness we just use “Call the Question” instead.