stdio.h File Reference

#include <stdarg.h>
#include <stddef.h>
#include <sys/types.h>

Go to the source code of this file.

Data Structures
struct	FILE

Macros
#define	SEEK_CUR   1
	Seek postition is relative to current position im file.
#define	SEEK_END   2
	Seek position is relative to end of file.
#define	SEEK_SET   3
	Seek position is relative to beginning of file.
#define	EOF   -1
	Represents EOF.

Functions
FILE *	fopen (char *filename, char *mode)
int	fgetc (FILE *stream)
int	getc (FILE *stream)
char *	fgets (char *str, int count, FILE *stream)
char *	gets (char *str)
size_t	fread (void *buffer, size_t size, size_t count, FILE *stream)
int	fputc (int c, FILE *stream)
int	putc (int c, FILE *stream)
int	fputs (const char *s, FILE *stream)
size_t	fwrite (void *buffer_ptr, size_t size, size_t count, FILE *stream)
int	puts (const char *s)
int	fprintf (FILE *stream, const char *format,...)
int	vfprintf (FILE *stream, const char *format, va_list arg)
int	printf (const char *format,...)
int	fseek (FILE *stream, long offset, int origin)
long	ftell (FILE *stream)
int	fclose (FILE *file)
int	feof (FILE *stream)
int	ferror (FILE *stream)
int	fflush (FILE *stream)
void	setbuf (FILE *restrict stream, char *restrict buf)
void	register_fs (const char *name, pid_t pid)
int	mount (char *file, char *type, char *path)

Variables
FILE *	stdin
	Standard input.
FILE *	stdout
	Standard output.
FILE *	stderr
	Standard error.

Function Documentation

fclose()

int fclose

(

FILE *

file

)

Closes a file

Parameters

file	The file to close

Returns

0 on success, EOF on failure

feof()

int feof

(

FILE *

stream

)

Returns the EOF indicator for a file

Parameters

stream

the file to check

Returns

the EOF indicator

ferror()

int ferror

(

FILE *

stream

)

Returns the error indicator for a file

Parameters

stream

the file to check

Returns

the error indicator

fflush()

int fflush

(

FILE *

stream

)

Flushes the buffer on a file

Parameters

stream

The file to flush the buffer of

Returns

0 on success, EOF on failure

fgetc()

int fgetc

(

FILE *

stream

)

Gets a character from a file

Parameters

stream

The file to read from

Returns

the read character, or EOF if the read fails

fgets()

char* fgets	(	char *	str,
		int	count,
		FILE *	stream
	)

Gets a newline delimeted string from a file

Parameters

str	The buffer to read into
count	The maximum size of the string to read
stream	The file to read from

Returns

the buffer

fopen()

FILE* fopen	(	char *	filename,
		char *	mode
	)

Opens a file with the specified mode

Parameters

filename	The path to the file to open
mode	The mode to open the file with (r,w,a,r+,w+,a+)

Returns

NULL if the file could not be opened, or a pointer to a FILE struct if the opening was sucessful.

fprintf()

int fprintf	(	FILE *	stream,
		const char *	format,
			...
	)

Format a string and writte it to a file

Parameters

stream	The fike to write to
format	The format string
...	The arguments for the format string

Returns

The number of bytes written

fputc()

int fputc	(	int	c,
		FILE *	stream
	)

Writes a character to a file

Parameters

c	The character to write
stream	The stream to write to

Returns

the written character, or EOF on failure

fputs()

int fputs	(	const char *	s,
		FILE *	stream
	)

Writes a string to a file

Parameters

s	The string to write
stream	The file to write to

Returns

0 on success, EOF on failure

fread()

size_t fread	(	void *	buffer,
		size_t	size,
		size_t	count,
		FILE *	stream
	)

Reads from a file

Parameters

buffer	The buffer to read into
size	The size of each elemnt to read
count	The number of elements to read
stream	The file to read from

Returns

the number of bytes read, or 0 on failure

fseek()

int fseek	(	FILE *	stream,
		long	offset,
		int	origin
	)

Seeks to a position in a file

Parameters

stream	The file to seek in
offset	The offset to seek to
origin	The origin of seeking (SEEK_CUR,SEEK_END,SEEK_SET)

Returns

0 on success, -1 on failure

ftell()

long ftell

(

FILE *

stream

)

Returns the postion in a file

Parameters

stream

The file to get the position in

Returns

the position on success, -1 on failure

fwrite()

size_t fwrite	(	void *	buffer_ptr,
		size_t	size,
		size_t	count,
		FILE *	stream
	)

Writes to a file

Parameters

buffer_ptr	The buffer to write
size	The size of each elemnt to write
count	The number of elements to write
stream	The file to write to

Returns

the number of bytes written, or 0 on failure

getc()

int getc

(

FILE *

stream

)

Gets a character from a file

Parameters

stream

The file to read from

Returns

the read character, or EOF if the read fails

gets()

char* gets

(

char *

str

)

Gets a newline delimeted string from stdin

Parameters

str	The buffer to read into

Returns

the buffer

Deprecated:

Gets is unsafe and vulnerable to a buffer overflow, as there is no bounds checking on the buffer.

mount()

int mount	(	char *	file,
		char *	type,
		char *	path
	)

Mounts a filesystem

Parameters

file	The file to mount
type	The type of the filesystem to mount
path	The path to mount the filesytem at

Returns

0 on success, 1 on failure

printf()

int printf	(	const char *	format,
			...
	)

Format a string and write it to stdout

Parameters

format	The format string
...	The arguments for the format string

Returns

The number of bytes written

putc()

int putc	(	int	c,
		FILE *	stream
	)

Writes a character to a file

Parameters

c	The character to write
stream	The stream to write to

Returns

the written character, or EOF on failure

puts()

int puts

(

const char *

s

)

Writes a string followed by a newline to stdin

Parameters

s	The string to write

Returns

0 on success, EOF on failure

register_fs()

void register_fs	(	const char *	name,
		pid_t	pid
	)

Registers a file system type with the VFS

Parameters

name	The name of the type to register
pid	The PID of the filesytem driver

setbuf()

void setbuf	(	FILE *restrict	stream,
		char *restrict	buf
	)

Assigns buffering to a file

When the buffer is not a null pointer, the buffer type is set to fully bufferd, and the buffer size is assumed to be at least BUFSIZ.

When the buffer is a null pointer, buffering is removed.

Parameters

stream	The file to assign buffering to
buf	The buffer to use

vfprintf()

int vfprintf	(	FILE *	stream,
		const char *	format,
		va_list	arg
	)

Format a string and writte it to a file

Parameters

stream	The fike to write to
format	The format string
arg	The arguments for the format string

Returns

The number of bytes written