匈牙利命名法 (For reference)

匈牙利命名法
變數名稱 = 屬性+類型+描述
屬性
" g_ 全域變數
" c_ 常數
" m_ 成員變數
類型
" n/ui int/unsigned int
" l/ ul long/unsigned long
" sh/us short/unsigned short
" f float
" d double
" ld long double
" ch char
" b boolean
" p pointer
" h handle
" str String
" w/dw WORD/DWORD
" b byte/unsigned char
" bl BOOL
描述
" Custom 自訂
" Src 來源
" Dst 目的
" Tmp 暫時

Other Reference:

Prefix	Data Type	Prefix	Data Type
c	char, TCHAR	bt	TBYTE, BYTE,
uc	UCHAR
s	short	us	USHORT
w	WORD	n	int, INT
u	UINT	l	LONG, long
dw	DWORD	ul	ULONG
fl	float	db	double
b	BOOL	f	bitwise flag fields
sz	ANSI string, terminated with a \0 character.	psz	PSTR
h	HANDLE	hmem	HGLOBAL, HLOCAL
hwnd	HWND	hfile	HFILE
hdc	HDC	hpen	HPEN
hfont	HFONT	hbmp	HBITMAP
hpal	HPALETTE	hmenu	HMENU
hicon	HICON	hinst	HINSTANCE
hcur	HCURSOR	hbr	HBRUSH
pt	POINT	rc	RECT
tm	TEXTMETRIC	lf	LOGFONT
bmp	BITMAPINFO	pal	PALETTEENTRY
cls	WNDCLASS	msg	MSG
rgb	RGBQUAD	clr	COLORREF
of	OFSTRUCT	ps	PAINTSTRUCT
cb	count of bytes	cx, cy	length in pixels
p	added for pointer to any type, e.g., ps, pdw, phicon, pof, ..., etc.	a	added for array of any type, e.g., as, adw, auc, ...
C	a big C in front of all C++ class names, the rest of the class name is a mix of big and small letters	m_	added in front of all C++ class member variables.
str	string
st	structure

suspend some seconds in the Linux/Windows

Linux
- sleep(n), , suspend n seconds
- usleep(n), suspend n * 10(-6) seconds

Windows
- Sleep(n) , suspend n * 10(-6) second

We can also use select to suspend n seconds m 10(-6) seconds

struct timeout tv;
tv.tv_sec = n;
tv.tv_usec = m;
select(0, NULL, NULL, NULL, &tv);

Then this function will suspend n seconds m 10(-6) seconds

Some hints in the C programming

1. Before using the character strings (either char array or malloc buffer), it is better to clean up all the buffer to zero (using memset(buf, 0, bufsize) or bzero function)

Question:
Sometimes we use the following declaration

char *mystr;

Then we can assign a string to the variable "mystr", like this. Is it valid to use this method?
mystr = "hello world";

Some C++ experience

1. type stringstream 的 member function
rdbuf Get/set the associated stringbuf object (public member function)

當呼叫過這一個rdbuf api 後, 原先stringstream 內的data 就會被刪除

str Get/set the associated string object (public member function)
如果只是想要顯示資料, 可以利用 str 這一個api 即可

至於其他的type, 如
ifstream
isstringstream
stream
等

ifstream public member functions
(constructor) Construct object and optionally open file (constructor member)
rdbuf Get the associated filebuf object (public member function)
is_open Check if a file is open (public member function)
open Open file (public member function)
close Close file (public member function)


istringstream public member functions
(constructor) Construct an object and optionally initialize its content (constructor member)
rdbuf Get/set the associated stringbuf object (public member function)
str Get/set the string content (public member function)

string

C 的特殊字元

- '\n' closes a line
- '\f' closes a page
- '\t' prints a tab wide spaces (whereas the definition of the tab
depends on the driver attached to the stream.)
- '\b' lets the logical cursor go a char backwards
whereas this cursor may be a the cursor on screen, the printhead,
a pinter inside the print buffer on the device or the driver....
- '\a' may ring a bell, a siren, or another device that
does require the attention of the operator or even does nothing when
no device that can be activated on that signal gets activated.
On a PC it will give traditionally a signal to the speaker or
play a wave file through the soudcard - or even do nothing or
something else.

C Operator Precedence and Associativity

http://www.difranco.net/cop2220/op-prec.htm

Operator
Description Associativity

()
[]
.
-> Parentheses (grouping)
Brackets (array subscript)
Member selection via object name
Member selection via pointer left-to-right

++ --
+ -
! ~
(type)
*
&
sizeof Unary preincrement/predecrement
Unary plus/minus
Unary logical negation/bitwise complement
Unary cast (change type)
Dereference
Address
Determine size in bytes right-to-left
* / % Multiplication/division/modulus left-to-right
+ - Addition/subtraction left-to-right
<< >> Bitwise shift left, Bitwise shift right left-to-right
< <=
> >= Relational less than/less than or equal to
Relational greater than/greater than or equal to left-to-right
== != Relational is equal to/is not equal to left-to-right
& Bitwise AND left-to-right
^ Bitwise exclusive OR left-to-right
| Bitwise inclusive OR left-to-right
&& Logical AND left-to-right
|| Logical OR left-to-right
?: Ternary conditional right-to-left
=
+= -=
*= /=
%= &=
^= |=
<<= >>= Assignment
Addition/subtraction assignment
Multiplication/division assignment
Modulus/bitwise AND assignment
Bitwise exclusive/inclusive OR assignment
Bitwise shift left/right assignment right-to-left
,
Comma (separate expressions) left-to-right