MSDN

PaLbI4

подскажите, как бы из MSDN поставить хелп только по стандартным функциям Си
З.Ы. что возвращает fopen, и какой формат ее вызова, какие параметры?

maggi14

int, вестимо. Дескриптор файла. Либо -1, если ошибка. Параметры LPCSTR и LPCSTR, первый - имя файла, второй - тип открывания. "w", "a", "r" с модификаторами "+" и "b"/"t".

kamputer

>int, вестимо.
хы

maggi14

а что же?

Chupa

не знаю, как у вас в мсдн, но даже в мане сказано "хы"

maggi14

от я дебил. Ну пофиг, один черт
последний год активно работал с библиотеками Dialogic - там int.

PaLbI4

что + означает, чет я все забыл совсем

maggi14

Короче, вот. Забудь, что я про возвращаемое значение писал.

Run-Time Library Reference	 	

fopen, _wfopen

Open a file.

FILE *fopen( 

   const char *filename,

   const char *mode 

);

FILE *_wfopen( 

   const wchar_t *filename,

   const wchar_t *mode 

);

Parameters

filename

Filename.

mode

Type of access permitted.

Return Value

Each of these functions returns a pointer to the open file. A null pointer 

value indicates an error. 

Remarks

The fopen function opens the file specified by filename. _wfopen is a 

wide-character version of fopen; the arguments to _wfopen are wide-character 

strings. _wfopen and fopen behave identically otherwise.

Generic-Text Routine Mappings

TCHAR.H routine 	_UNICODE & _MBCS not defined	_MBCS defined	

_UNICODE defined	

_tfopen	fopen	fopen	_wfopen	

The character string mode specifies the type of access requested for the file, 

as follows: 

"r"

Opens for reading. If the file does not exist or cannot be found, the fopen 

call fails.

"w"

Opens an empty file for writing. If the given file exists, its contents are 

destroyed.

"a"

Opens for writing at the end of the file (appending) without removing the EOF 

marker before writing new data to the file; creates the file first if it 

doesn't exist.

"r+"

Opens for both reading and writing. (The file must exist.)

"w+"

Opens an empty file for both reading and writing. If the given file exists, its 

contents are destroyed.

"a+"

Opens for reading and appending; the appending operation includes the removal 

of the EOF marker before new data is written to the file and the EOF marker is 

restored after writing is complete; creates the file first if it doesn't exist.

When a file is opened with the "a" or "a+" access type, all write operations 

occur at the end of the file. The file pointer can be repositioned using fseek 

or rewind, but is always moved back to the end of the file before any write 

operation is carried out. Thus, existing data cannot be overwritten.

The "a" mode does not remove the EOF marker before appending to the file. After 

appending has occurred, the MS-DOS TYPE command only shows data up to the 

original EOF marker and not any data appended to the file. The "a+" mode does 

remove the EOF marker before appending to the file. After appending, the MS-DOS 

TYPE command shows all data in the file. The "a+" mode is required for 

appending to a stream file that is terminated with the CTRL+Z EOF marker.

When the "r+", "w+", or "a+" access type is specified, both reading and writing 

are allowed (the file is said to be open for "update"). However, when you 

switch between reading and writing, there must be an intervening fflush, 

fsetpos, fseek, or rewind operation. The current position can be specified for 

the fsetpos or fseek operation, if desired.

In addition to the above values, the following characters can be included in 

mode to specify the translation mode for newline characters: 

t

Open in text (translated) mode. In this mode, CTRL+Z is interpreted as an 

end-of-file character on input. In files opened for reading/writing with "a+", 

fopen checks for a CTRL+Z at the end of the file and removes it, if possible. 

This is done because using fseek and ftell to move within a file that ends with 

a CTRL+Z, may cause fseek to behave improperly near the end of the file. 

Also, in text mode, carriage return–linefeed combinations are translated into 

single linefeeds on input, and linefeed characters are translated to carriage 

return–linefeed combinations on output. When a Unicode stream-I/O function 

operates in text mode (the default the source or destination stream is 

assumed to be a sequence of multibyte characters. Therefore, the Unicode 

stream-input functions convert multibyte characters to wide characters (as if 

by a call to the mbtowc function). For the same reason, the Unicode 

stream-output functions convert wide characters to multibyte characters (as if 

by a call to the wctomb function). 

b

Open in binary (untranslated) mode; translations involving carriage-return and 

linefeed characters are suppressed. 

If t or b is not given in mode, the default translation mode is defined by the 

global variable _fmode. If t or b is prefixed to the argument, the function 

fails and returns NULL. 

For more information about using text and binary modes in Unicode and multibyte 

stream-I/O, see Text and Binary Mode File I/O and Unicode Stream I/O in Text 

and Binary Modes. 

c

Enable the commit flag for the associated filename so that the contents of the 

file buffer are written directly to disk if either fflush or _flushall is 

called.

n

Reset the commit flag for the associated filename to "no-commit." This is the 

default. It also overrides the global commit flag if you link your program with 

COMMODE.OBJ. The global commit flag default is "no-commit" unless you 

explicitly link your program with COMMODE.OBJ.

S

Specifies that caching is optimized for, but not restricted to, sequential 

access from disk.

R

Specifies that caching is optimized for, but not restricted to, random access 

from disk.

T

Specifies a file as temporary. If possible, it is not flushed to disk.

D

Specifies a file as temporary. It is deleted when the last file pointer is 

closed.

Valid characters for the mode string used in fopen and _fdopen correspond to 

oflag arguments used in _open and _sopen, as follows.

Characters in mode string	

Equivalent oflag value for _open/_sopen

a	_O_WRONLY | _O_APPEND (usually _O_WRONLY | _O_CREAT | _O_APPEND)	

a+	_O_RDWR | _O_APPEND (usually _O_RDWR | _O_APPEND | _O_CREAT )	

R	_O_RDONLY	

r+	_O_RDWR	

W	_O_WRONLY (usually _O_WRONLY | _O_CREAT | _O_TRUNC)	

W+	_O_RDWR (usually _O_RDWR | _O_CREAT | _O_TRUNC)	

B	_O_BINARY	

T	_O_TEXT	

C	None	

N	None	

S	_O_SEQUENTIAL	

R	_O_RANDOM	

T	_O_SHORTLIVED	

D	_O_TEMPORARY	

If you are using rb mode, won't need to port your code, and expect to read a 

lot of the file and/or don't care about network performance, memory mapped 

Win32 files might is also an option.

Requirements

Function	Required header	Compatibility	

fopen	<stdio.h>	ANSI, Win 98, Win Me, Win NT, Win 2000, Win XP	

_wfopen	<stdio.h> or <wchar.h>	Win NT, Win 2000, Win XP	

For additional compatibility information, see Compatibility in the Introduction.

Libraries

All versions of the C run-time libraries.

The c, n, and t mode options are Microsoft extensions for fopen and _fdopen and 

should not be used where ANSI portability is desired.

Example

// crt_fopen.c

/* This program opens two files. It uses

 * fclose to close the first file and

 * _fcloseall to close all remaining files.

 */

#include <stdio.h>

FILE *stream, *stream2;

int main( void )

{

   int numclosed;

   /* Open for read (will fail if file "crt_fopen.c" does not exist) */

   if( (stream  = fopen( "crt_fopen.c", "r"  == NULL )

      printf( "The file 'crt_fopen.c' was not opened\n" );

   else

      printf( "The file 'crt_fopen.c' was opened\n" );

   /* Open for write */

   if( (stream2 = fopen( "data2", "w+"  == NULL

PaLbI4

Thnxs