diff options
| -rw-r--r-- | bash.html.markdown | 4 | ||||
| -rw-r--r-- | c.html.markdown | 51 | ||||
| -rw-r--r-- | c.html.markdown.orig | 641 |
3 files changed, 667 insertions, 29 deletions
diff --git a/bash.html.markdown b/bash.html.markdown index 1473e669..2faa4988 100644 --- a/bash.html.markdown +++ b/bash.html.markdown @@ -53,10 +53,10 @@ else echo "And this is not" fi -# And the usual while loop: +# while loop: while [true] do - echo "put loop content here..." + echo "loop body here..." break done diff --git a/c.html.markdown b/c.html.markdown index 68ef7f03..2a65d82c 100644 --- a/c.html.markdown +++ b/c.html.markdown @@ -39,7 +39,7 @@ Multi-line comments look like this. They work in C89 as well. //print formatting: "%d" // integer -"%3d" // minimum length of 3 digits for integer (right justifies text) +"%3d" // integer with minimum of length 3 digits (right justifies text) "%s" // string "%f" // float "%ld" // long @@ -51,7 +51,7 @@ Multi-line comments look like this. They work in C89 as well. "%o" // octal "%%" // prints % -// Constants: use #define keyword, no semicolon at end. +// Constants: #define <keyword> (no semicolon at end) #define DAYS_IN_YEAR = 365 //enumeration constants are also ways to declare constants. @@ -62,7 +62,6 @@ enum days {SUN = 1, MON, TUE, WED, THU, FRI, SAT}; #include <stdlib.h> #include <stdio.h> #include <string.h> -#include <ctype.h> // (File names between <angle brackets> are headers from the C standard library.) // For your own headers, use double quotes instead of angle brackets: @@ -111,7 +110,7 @@ int main() { unsigned int ux_int; unsigned long long ux_long_long; - // chars inside single quotes '*' are integers in your character set. + // chars inside single quotes are integers in machine's character set. '0' //==> 48 on the ASCII character set. 'A' //==> 65 on the ASCII character set. @@ -226,20 +225,14 @@ int main() { 0 || 1; // => 1 (Logical or) 0 || 0; // => 0 - //Conditional expression ( ?: ) + //Conditional expression ( ? : ) int a, b, z; - z = (a > b) ? a : b; // z = max(a, b); + z = (a > b) ? a : b; // "if a > b return a, else return b." //Increment and decrement operators: - int j = 0; - char s[]; - int w = 0; - j++; //difference between postfix and prefix explained below - ++j; // in string example. - j--; - --j; s[j++]; //returns value of j to s THEN increments value of j. s[++j]; //increments value of j THEN returns value of j to s. + // same with j-- and --j // Bitwise operators! ~0x0F; // => 0xF0 (bitwise negation, "1's complement") @@ -267,12 +260,6 @@ int main() { printf("I print\n"); } - // Notes: - // Loops MUST always have a body. If no body is needed, do this: - for (i = 0; i <= 5; i++) { - ; // use semicolon to act as the body (null statement) - } - // While loops exist int ii = 0; while (ii < 10) { //ANY value not zero is true. @@ -297,6 +284,12 @@ int main() { printf("\n"); + // *****NOTES*****: + // Loops MUST always have a body. If no body is needed, do: + for (i = 0; i <= 5; i++) { + ; // use semicolon to act as the body (null statement) + } + // branching with multiple choices: switch() switch (some_integral_expression) { case 0: // labels need to be integral *constant* epxressions @@ -449,17 +442,19 @@ int add_two_ints(int x1, int x2) } // Must declare a 'function prototype' before main() when creating functions -// in file. void getInt(char c); // function prototype -int main() { +int main() { // main function return 0; } void getInt(char w) { //parameter name does not need to match function prototype ; } -//if function takes no parameters, do: int getInt(void); for function prototype -// and for the function declaration: int getInt(void) {} -// this is to keep compatibility with older versions of C. + +//if function takes no parameters, do: +int getInt(void); for function prototype +// and for the function declaration: +int getInt(void) {} +// (this is to keep compatibility with older versions of C). /* Functions are call by value. So when a function is called, the arguments passed @@ -485,11 +480,13 @@ void str_reverse(char *str_in) } } +///////////////////////////////////// // Built in functions: +///////////////////////////////////// // from stdio.h: -int c = getchar(); //reads character from input. If input = hi, only h is read. -// getchar() can be stored into int or char. I am using int because -// char is not large enough to store EOF used below. +// getchar() +int c = getchar(); //reads character from input. +// If input = hi, 'h' is returned then next call, 'i' returned. while ((c = getchar()) != EOF) { // EOF constant "end of file". // Linux: CTRL+D, Windows: CTRL+X // must have () around getchar() as != is run before =. diff --git a/c.html.markdown.orig b/c.html.markdown.orig new file mode 100644 index 00000000..47996cb2 --- /dev/null +++ b/c.html.markdown.orig @@ -0,0 +1,641 @@ +--- +language: c +filename: learnc.c +contributors: + - ["Adam Bard", "http://adambard.com/"] + - ["Árpád Goretity", "http://twitter.com/H2CO3_iOS"] + +--- + +Ah, C. Still **the** language of modern high-performance computing. + +C is the lowest-level language most programmers will ever use, but +it more than makes up for it with raw speed. Just be aware of its manual +memory management and C will take you as far as you need to go. + +```c +// Single-line comments start with // - only available in C99 and later. + +/* +Multi-line comments look like this. They work in C89 as well. +*/ + +//Special characters: +'\a' // alert (bell) character +'\n' // newline character +'\t' // tab character (left justifies text) +'\v' // vertical tab +'\f' // new page (formfeed) +'\r' // carriage return +'\b' // backspace character +'\0' // null character. Usually put at end of strings in C lang. + // hello\n\0. \0 used by convention to mark end of string. +'\\' // backspace +'\?' // question mark +'\'' // single quote +'\"' // double quote +'\xhh' // hexadecimal number. Example: '\xb' = vertical tab character +'\ooo' // octal number. Example: '\013' = vertical tab character + +//print formatting: +"%d" // integer +"%3d" // integer with minimum of length 3 digits (right justifies text) +"%s" // string +"%f" // float +"%ld" // long +"%3.2f" // minimum 3 digits left and 2 digits right decimal float +"%7.4s" // (can do with strings too) +"%c" // char +"%p" // pointer +"%x" // hexidecimal +"%o" // octal +"%%" // prints % + +// Constants: #define <keyword> (no semicolon at end) +#define DAYS_IN_YEAR = 365 + +//enumeration constants are also ways to declare constants. +enum days {SUN = 1, MON, TUE, WED, THU, FRI, SAT}; +// MON gets 2 automatically, TUE gets 3, etc. + +// Import headers with #include +#include <stdlib.h> +#include <stdio.h> +#include <string.h> + +// (File names between <angle brackets> are headers from the C standard library.) +// For your own headers, use double quotes instead of angle brackets: +#include "my_header.h" + +// Declare function signatures in advance in a .h file, or at the top of +// your .c file. +void function_1(); +void function_2(); + +// Your program's entry point is a function called +// main with an integer return type. +int main() { + // print output using printf, for "print formatted" + // %d is an integer, \n is a newline + printf("%d\n", 0); // => Prints 0 + // All statements must end with a semicolon + + /////////////////////////////////////// + // Types + /////////////////////////////////////// + + // ints are usually 4 bytes + int x_int = 0; + + // shorts are usually 2 bytes + short x_short = 0; + + // chars are guaranteed to be 1 byte + char x_char = 0; + char y_char = 'y'; // Char literals are quoted with '' + + // longs are often 4 to 8 bytes; long longs are guaranteed to be at least + // 64 bits + long x_long = 0; + long long x_long_long = 0; + + // floats are usually 32-bit floating point numbers + float x_float = 0.0; + + // doubles are usually 64-bit floating-point numbers + double x_double = 0.0; + + // Integral types may be unsigned. + unsigned short ux_short; + unsigned int ux_int; + unsigned long long ux_long_long; + + // chars inside single quotes are integers in machine's character set. + '0' //==> 48 on the ASCII character set. + 'A' //==> 65 on the ASCII character set. + + // sizeof(T) gives you the size of a variable with type T in bytes + // sizeof(obj) yields the size of the expression (variable, literal, etc.). + printf("%zu\n", sizeof(int)); // => 4 (on most machines with 4-byte words) + + + // If the argument of the `sizeof` operator an expression, then its argument + // is not evaluated (except VLAs (see below)). + // The value it yields in this case is a compile-time constant. + int a = 1; + size_t size = sizeof(a++); // a++ is not evaluated + printf("sizeof(a++) = %zu where a = %d\n", size, a); + // prints "sizeof(a++) = 4 where a = 1" (on a 32-bit architecture) + + // Arrays must be initialized with a concrete size. + char my_char_array[20]; // This array occupies 1 * 20 = 20 bytes + int my_int_array[20]; // This array occupies 4 * 20 = 80 bytes + // (assuming 4-byte words) + + + // You can initialize an array to 0 thusly: + char my_array[20] = {0}; + + // Indexing an array is like other languages -- or, + // rather, other languages are like C + my_array[0]; // => 0 + + // Arrays are mutable; it's just memory! + my_array[1] = 2; + printf("%d\n", my_array[1]); // => 2 + + // In C99 (and as an optional feature in C11), variable-length arrays (VLAs) + // can be declared as well. The size of such an array need not be a compile + // time constant: + printf("Enter the array size: "); // ask the user for an array size + char buf[0x100]; + fgets(buf, sizeof buf, stdin); + + // strtoul parses a string to an unsigned integer + size_t size = strtoul(buf, NULL, 10); + int var_length_array[size]; // declare the VLA + printf("sizeof array = %zu\n", sizeof var_length_array); + + // A possible outcome of this program may be: + // > Enter the array size: 10 + // > sizeof array = 40 + + // Strings are just arrays of chars terminated by a NUL (0x00) byte, + // represented in strings as the special character '\0'. + // (We don't have to include the NUL byte in string literals; the compiler + // inserts it at the end of the array for us.) + char a_string[20] = "This is a string"; + printf("%s\n", a_string); // %s formats a string + + printf("%d\n", a_string[16]); // => 0 + // i.e., byte #17 is 0 (as are 18, 19, and 20) + + // If we have characters between single quotes, that's a character literal. + // It's of type `int`, and *not* `char` (for historical reasons). + int cha = 'a'; // fine + char chb = 'a'; // fine too (implicit conversion from int to char) + + /////////////////////////////////////// + // Operators + /////////////////////////////////////// + + int i1 = 1, i2 = 2; // Shorthand for multiple declaration + float f1 = 1.0, f2 = 2.0; + + //more shorthands: + int a, b, c; + a = b = c = 0; + + // Arithmetic is straightforward + i1 + i2; // => 3 + i2 - i1; // => 1 + i2 * i1; // => 2 + i1 / i2; // => 0 (0.5, but truncated towards 0) + + f1 / f2; // => 0.5, plus or minus epsilon + // Floating-point numbers and calculations are not exact + + // Modulo is there as well + 11 % 3; // => 2 + + // Comparison operators are probably familiar, but + // there is no boolean type in c. We use ints instead. + // (Or _Bool or bool in C99.) + // 0 is false, anything else is true. (The comparison + // operators always yield 0 or 1.) + 3 == 2; // => 0 (false) + 3 != 2; // => 1 (true) + 3 > 2; // => 1 + 3 < 2; // => 0 + 2 <= 2; // => 1 + 2 >= 2; // => 1 + + // C is not Python - comparisons don't chain. + int a = 1; + // WRONG: + int between_0_and_2 = 0 < a < 2; + // Correct: + int between_0_and_2 = 0 < a && a < 2; + + // Logic works on ints + !3; // => 0 (Logical not) + !0; // => 1 + 1 && 1; // => 1 (Logical and) + 0 && 1; // => 0 + 0 || 1; // => 1 (Logical or) + 0 || 0; // => 0 + + //Conditional expression ( ? : ) + int a, b, z; + z = (a > b) ? a : b; // "if a > b return a, else return b." + + //Increment and decrement operators: + s[j++]; //returns value of j to s THEN increments value of j. + s[++j]; //increments value of j THEN returns value of j to s. + // same with j-- and --j + + // Bitwise operators! + ~0x0F; // => 0xF0 (bitwise negation, "1's complement") + 0x0F & 0xF0; // => 0x00 (bitwise AND) + 0x0F | 0xF0; // => 0xFF (bitwise OR) + 0x04 ^ 0x0F; // => 0x0B (bitwise XOR) + 0x01 << 1; // => 0x02 (bitwise left shift (by 1)) + 0x02 >> 1; // => 0x01 (bitwise right shift (by 1)) + + // Be careful when shifting signed integers - the following are undefined: + // - shifting into the sign bit of a signed integer (int a = 1 << 32) + // - left-shifting a negative number (int a = -1 << 2) + // - shifting by an offset which is >= the width of the type of the LHS: + // int a = 1 << 32; // UB if int is 32 bits wide + + /////////////////////////////////////// + // Control Structures + /////////////////////////////////////// + + if (0) { + printf("I am never run\n"); + } else if (0) { + printf("I am also never run\n"); + } else { + printf("I print\n"); + } + + // While loops exist + int ii = 0; + while (ii < 10) { //ANY value not zero is true. + printf("%d, ", ii++); // ii++ increments ii AFTER using it's current value. + } // => prints "0, 1, 2, 3, 4, 5, 6, 7, 8, 9, " + + printf("\n"); + + int kk = 0; + do { + printf("%d, ", kk); + } while (++kk < 10); // ++kk increments kk BEFORE using it's current value. + // => prints "0, 1, 2, 3, 4, 5, 6, 7, 8, 9, " + + printf("\n"); + + // For loops too + int jj; + for (jj=0; jj < 10; jj++) { + printf("%d, ", jj); + } // => prints "0, 1, 2, 3, 4, 5, 6, 7, 8, 9, " + + printf("\n"); + + // *****NOTES*****: + // Loops MUST always have a body. If no body is needed, do: + for (i = 0; i <= 5; i++) { + ; // use semicolon to act as the body (null statement) + } + + // branching with multiple choices: switch() + switch (some_integral_expression) { + case 0: // labels need to be integral *constant* epxressions + do_stuff(); + break; // if you don't break, control flow falls over labels + case 1: + do_something_else(); + break; + default: + // if `some_integral_expression` didn't match any of the labels + fputs("error!\n", stderr); + exit(-1); + break; + } + + + /////////////////////////////////////// + // Typecasting + /////////////////////////////////////// + + // Every value in C has a type, but you can cast one value into another type + // if you want (with some constraints). + + int x_hex = 0x01; // You can assign vars with hex literals + + // Casting between types will attempt to preserve their numeric values + printf("%d\n", x_hex); // => Prints 1 + printf("%d\n", (short) x_hex); // => Prints 1 + printf("%d\n", (char) x_hex); // => Prints 1 + + // Types will overflow without warning + printf("%d\n", (unsigned char) 257); // => 1 (Max char = 255 if char is 8 bits long) + + // For determining the max value of a `char`, a `signed char` and an `unisigned char`, + // respectively, use the CHAR_MAX, SCHAR_MAX and UCHAR_MAX macros from <limits.h> + + // Integral types can be cast to floating-point types, and vice-versa. + printf("%f\n", (float)100); // %f formats a float + printf("%lf\n", (double)100); // %lf formats a double + printf("%d\n", (char)100.0); + + /////////////////////////////////////// + // Pointers + /////////////////////////////////////// + + // A pointer is a variable declared to store a memory address. Its declaration will + // also tell you the type of data it points to. You can retrieve the memory address + // of your variables, then mess with them. + + int x = 0; + printf("%p\n", (void *)&x); // Use & to retrieve the address of a variable + // (%p formats an object pointer of type void *) + // => Prints some address in memory; + + + // Pointers start with * in their declaration + int *px, not_a_pointer; // px is a pointer to an int + px = &x; // Stores the address of x in px + printf("%p\n", (void *)px); // => Prints some address in memory + printf("%zu, %zu\n", sizeof(px), sizeof(not_a_pointer)); + // => Prints "8, 4" on a typical 64-bit system + + // To retreive the value at the address a pointer is pointing to, + // put * in front to de-reference it. + // Note: yes, it may be confusing that '*' is used for _both_ declaring a + // pointer and dereferencing it. + printf("%d\n", *px); // => Prints 0, the value of x + + // You can also change the value the pointer is pointing to. + // We'll have to wrap the de-reference in parenthesis because + // ++ has a higher precedence than *. + (*px)++; // Increment the value px is pointing to by 1 + printf("%d\n", *px); // => Prints 1 + printf("%d\n", x); // => Prints 1 + + // Arrays are a good way to allocate a contiguous block of memory + int x_array[20]; //declares array of size 20 (cannot change size) + int xx; + for (xx = 0; xx < 20; xx++) { + x_array[xx] = 20 - xx; + } // Initialize x_array to 20, 19, 18,... 2, 1 + + // Declare a pointer of type int and initialize it to point to x_array + int* x_ptr = x_array; + // x_ptr now points to the first element in the array (the integer 20). + // This works because arrays often decay into pointers to their first element. + // For example, when an array is passed to a function or is assigned to a pointer, + // it decays into (implicitly converted to) a pointer. + // Exceptions: when the array is the argument of the `&` (address-od) operator: + int arr[10]; + int (*ptr_to_arr)[10] = &arr; // &arr is NOT of type `int *`! + // It's of type "pointer to array" (of ten `int`s). + // or when the array is a string literal used for initializing a char array: + char arr[] = "foobarbazquirk"; + // or when it's the argument of the `sizeof` or `alignof` operator: + int arr[10]; + int *ptr = arr; // equivalent with int *ptr = &arr[0]; + printf("%zu %zu\n", sizeof arr, sizeof ptr); // probably prints "40, 4" or "40, 8" + + + // Pointers are incremented and decremented based on their type + // (this is called pointer arithmetic) + printf("%d\n", *(x_ptr + 1)); // => Prints 19 + printf("%d\n", x_array[1]); // => Prints 19 + + // You can also dynamically allocate contiguous blocks of memory with the + // standard library function malloc, which takes one argument of type size_t + // representing the number of bytes to allocate (usually from the heap, although this + // may not be true on e. g. embedded systems - the C standard says nothing about it). + int *my_ptr = malloc(sizeof(*my_ptr) * 20); + for (xx = 0; xx < 20; xx++) { + *(my_ptr + xx) = 20 - xx; // my_ptr[xx] = 20-xx + } // Initialize memory to 20, 19, 18, 17... 2, 1 (as ints) + + // Dereferencing memory that you haven't allocated gives + // "unpredictable results" - the program is said to invoke "undefined behavior" + printf("%d\n", *(my_ptr + 21)); // => Prints who-knows-what? It may even crash. + + // When you're done with a malloc'd block of memory, you need to free it, + // or else no one else can use it until your program terminates + // (this is called a "memory leak"): + free(my_ptr); + + // Strings are arrays of char, but they are usually represented as a + // pointer-to-char (which is a pointer to the first element of the array). + // It's good practice to use `const char *' when referring to a string literal, + // since string literals shall not be modified (i. e. "foo"[0] = 'a' is ILLEGAL.) + const char *my_str = "This is my very own string literal"; + printf("%c\n", *my_str); // => 'T' + + // This is not the case if the string is an array + // (potentially initialized with a string literal) + // that resides in writable memory, as in: + char foo[] = "foo"; + foo[0] = 'a'; // this is legal, foo now contains "aoo" + + function_1(); +} // end main function + +/////////////////////////////////////// +// Functions +/////////////////////////////////////// + +// Function declaration syntax: +// <return type> <function name>(<args>) + +int add_two_ints(int x1, int x2) +{ + return x1 + x2; // Use return to return a value +} + +<<<<<<< HEAD +// Must declare a 'function prototype' before main() when creating functions +// in file. +======= +// Must declare a 'funtion prototype' when creating functions before main() +>>>>>>> f28d33fb187bc834e6e2956117039f9abe3b6d9b +void getInt(char c); // function prototype +int main() { // main function + return 0; +} +void getInt(char w) { //parameter name does not need to match function prototype + ; +} + +//if function takes no parameters, do: +int getInt(void); for function prototype +// and for the function declaration: +int getInt(void) {} +// (this is to keep compatibility with older versions of C). + +/* +Functions are call by value. So when a function is called, the arguments passed +to the function are copies of original arguments (except arrays). Anything you +do to your arguments do not change the value of the actual argument where the +function was called. + +You can use pointers if you need to edit the original argument values. + +Example: in-place string reversal +*/ + +// A void function returns no value +void str_reverse(char *str_in) +{ + char tmp; + int ii = 0; + size_t len = strlen(str_in); // `strlen()` is part of the c standard library + for (ii = 0; ii < len / 2; ii++) { + tmp = str_in[ii]; + str_in[ii] = str_in[len - ii - 1]; // ii-th char from end + str_in[len - ii - 1] = tmp; + } +} + +///////////////////////////////////// +// Built in functions: +///////////////////////////////////// +// from stdio.h: +// getchar() +int c = getchar(); //reads character from input. +// If input = hi, 'h' is returned then next call, 'i' returned. +while ((c = getchar()) != EOF) { // EOF constant "end of file". + // Linux: CTRL+D, Windows: CTRL+X + // must have () around getchar() as != is run before =. + putchar(c); //prints character (without newline at end) + char c = getchar(); +} + +//if referring to external variables outside function, must use extern keyword. +int i = 0; +void testFunc() { + extern int i; //i here is now using external variable i +} + +/* +char c[] = "This is a test."; +str_reverse(c); +printf("%s\n", c); // => ".tset a si sihT" +*/ + +/////////////////////////////////////// +// User-defined types and structs +/////////////////////////////////////// + +// Typedefs can be used to create type aliases +typedef int my_type; +my_type my_type_var = 0; + +// Structs are just collections of data, the members are allocated sequentially, +// in the order they are written: +struct rectangle { + int width; + int height; +}; + +// It's not generally true that +// sizeof(struct rectangle) == sizeof(int) + sizeof(int) +// due to potential padding between the structure members (this is for alignment +// reasons). [1] + +void function_1() +{ + struct rectangle my_rec; + + // Access struct members with . + my_rec.width = 10; + my_rec.height = 20; + + // You can declare pointers to structs + struct rectangle *my_rec_ptr = &my_rec; + + // Use dereferencing to set struct pointer members... + (*my_rec_ptr).width = 30; + + // ... or even better: prefer the -> shorthand for the sake of readability + my_rec_ptr->height = 10; // Same as (*my_rec_ptr).height = 10; +} + +// You can apply a typedef to a struct for convenience +typedef struct rectangle rect; + +int area(rect r) +{ + return r.width * r.height; +} + +// if you have large structs, you can pass them "by pointer" to avoid copying +// the whole struct: +int area(const rect *r) +{ + return r->width * r->height; +} + +/////////////////////////////////////// +// Function pointers +/////////////////////////////////////// +/* +At runtime, functions are located at known memory addresses. Function pointers are +much like any other pointer (they just store a memory address), but can be used +to invoke functions directly, and to pass handlers (or callback functions) around. +However, definition syntax may be initially confusing. + +Example: use str_reverse from a pointer +*/ +void str_reverse_through_pointer(char *str_in) { + // Define a function pointer variable, named f. + void (*f)(char *); // Signature should exactly match the target function. + f = &str_reverse; // Assign the address for the actual function (determined at runtime) + // f = str_reverse; would work as well - functions decay into pointers, similar to arrays + (*f)(str_in); // Just calling the function through the pointer + // f(str_in); // That's an alternative but equally valid syntax for calling it. +} + +/* +As long as function signatures match, you can assign any function to the same pointer. +Function pointers are usually typedef'd for simplicity and readability, as follows: +*/ + +typedef void (*my_fnp_type)(char *); + +// Then used when declaring the actual pointer variable: +// ... +// my_fnp_type f; + + +/////////////////////////////////////// +// Order of Evaluation +/////////////////////////////////////// + +//---------------------------------------------------// +// Operators | Associativity // +//---------------------------------------------------// +// () [] -> . | left to right // +// ! ~ ++ -- + = *(type)sizeof | right to left // +// * / % | left to right // +// + - | left to right // +// << >> | left to right // +// < <= > >= | left to right // +// == != | left to right // +// & | left to right // +// ^ | left to right // +// | | left to right // +// && | left to right // +// || | left to right // +// ?: | right to left // +// = += -= *= /= %= &= ^= |= <<= >>= | right to left // +// , | left to right // +//---------------------------------------------------// + +``` + +## Further Reading + +Best to find yourself a copy of [K&R, aka "The C Programming Language"](https://en.wikipedia.org/wiki/The_C_Programming_Language) +It is *the* book about C, written by the creators of C. Be careful, though - it's ancient and it contains some +inaccuracies (well, ideas that are not considered good anymore) or now-changed practices. + +Another good resource is [Learn C the hard way](http://c.learncodethehardway.org/book/). + +If you have a question, read the [compl.lang.c Frequently Asked Questions](http://c-faq.com). + +It's very important to use proper spacing, indentation and to be consistent with your coding style in general. +Readable code is better than clever code and fast code. For a good, sane coding style to adopt, see the +[Linux kernel coding stlye](https://www.kernel.org/doc/Documentation/CodingStyle). + +Other than that, Google is your friend. + +[1] http://stackoverflow.com/questions/119123/why-isnt-sizeof-for-a-struct-equal-to-the-sum-of-sizeof-of-each-member |