Filesystem header. More...

Collaboration diagram for Filesystem IO:

Detailed Description

Filesystem header.

Data Structures
struct	pollfd_t
	Poll file descriptor structure. More...

struct	vattr_t
	Vnode attributes structure. More...

struct	stat_t
	Stat type. More...

struct	dirent_t
	Directory entry struct. More...

Macros
#define	STDIN_FILENO 0
	Standard input file descriptor.

#define	STDOUT_FILENO 1
	Standard output file descriptor.

#define	STDERR_FILENO 2
	Standard error file descriptor.

#define	PIPE_READ 0
	Pipe read end.

#define	PIPE_WRITE 1
	Pipe write end.

#define	F_MAX_SIZE 512
	Maximum buffer size for the `F()` macro.

#define	F(format, ...)
	Allocates a formatted string on the stack.

#define	POLL_SPECIAL (POLLERR \| POLLHUP \| POLLNVAL)
	Poll event values that will always be checked and included even if not specified.

#define	KEY_MAX 128
	Maximum size of a key generated by `share()`.

#define	KEY_128BIT 25
	The size of a buffer needed to hold a 128-bit key.

#define	KEY_256BIT 45
	The size of a buffer needed to hold a 256-bit key.

#define	KEY_512BIT 89
	The size of a buffer needed to hold a 512-bit key.

#define	RETRY_EINTR(expr)
	Macro to automatically retry a function that returns an integer if it errors and `errno == EINTR`.

#define	RETRY_EINTR_PTR(expr)
	Macro to automatically retry a function that returns a pointer if it errors and `errno == EINTR`.

Typedefs
typedef uint8_t	seek_origin_t
	Type for the `seek()` origin argument.

typedef uint64_t	sbid_t
	A suberblock identifier that uniquely identifies a superblock within the system.

Enumerations
enum	poll_events_t { POLLNONE = 0 , POLLIN = (1 << 0) , POLLOUT = (1 << 1) , POLLERR = (1 << 2) , POLLHUP = (1 << 3) , POLLNVAL = (1 << 4) }
	Poll events type. More...

enum	vtype_t { VREG , VDIR , VSYMLINK }
	Vnode type enum. More...

enum	dirent_flags_t { DIRENT_NONE = 0 , DIRENT_MOUNTED = 1 << 0 }
	Directory entry flags. More...

Functions
fd_t	open (const char *path)
	System call for opening files.

uint64_t	open2 (const char *path, fd_t fd[2])
	System call for opening 2 file descriptors from one file.

fd_t	openat (fd_t from, const char *path)
	System call for opening files relative to another file descriptor.

uint64_t	close (fd_t fd)
	System call for closing files.

size_t	read (fd_t fd, void *buffer, size_t count)
	System call for reading from files.

char *	reads (fd_t fd)
	Wrapper for reading a file directly into a null-terminated string.

size_t	readfile (const char path, void buffer, size_t count, size_t offset)
	Wrapper for reading a file directly using a path.

char *	readfiles (const char *path)
	Wrapper for reading an entire file directly into a null-terminated string.

size_t	write (fd_t fd, const void *buffer, size_t count)
	System call for writing to files.

size_t	writes (fd_t fd, const char *string)
	Wrapper for writing a null-terminated string to a file.

size_t	writefile (const char path, const void buffer, size_t count, size_t offset)
	Wrapper for writing to a file directly using a path.

size_t	writefiles (const char path, const char string)
	Wrapper for writing a null-terminated string directly to a file using a path.

uint64_t	scan (fd_t fd, const char *format,...)
	Wrapper for reading from a file descriptor using scan formatting.

uint64_t	vscan (fd_t fd, const char *format, va_list args)
	Wrapper for reading from a file descriptor using scan formatting with `va_list`.

uint64_t	scanfile (const char path, const char format,...)
	Wrapper for reading from a file path using scan formatting.

uint64_t	vscanfile (const char path, const char format, va_list args)
	Wrapper for reading from a file path using scan formatting with `va_list`.

size_t	seek (fd_t fd, ssize_t offset, seek_origin_t origin)
	System call for changing the file offset.

uint64_t	chdir (const char *path)
	System call for changing the cwd.

uint64_t	poll (pollfd_t *fds, uint64_t amount, clock_t timeout)
	System call for polling files.

poll_events_t	poll1 (fd_t fd, poll_events_t events, clock_t timeout)
	Wrapper for polling one file.

uint64_t	stat (const char path, stat_t stat)
	System call for retrieving info about a file or directory.

uint64_t	ioctl (fd_t fd, uint64_t request, void *argp, size_t size)
	System call for extended driver behaviour.

fd_t	dup (fd_t oldFd)
	System call for duplicating file descriptors.

fd_t	dup2 (fd_t oldFd, fd_t newFd)
	System call for duplicating file descriptors, with a destination.

size_t	getdents (fd_t fd, dirent_t *buffer, uint64_t count)
	System call for reading directory entires.

size_t	readdir (fd_t fd, dirent_t *buffer, uint64_t count)
	Helper for reading all directory entries.

uint64_t	mkdir (const char *path)
	Wrapper for creating a directory.

uint64_t	rmdir (const char *path)
	Wrapper for removing a directory.

uint64_t	link (const char oldPath, const char newPath)
	System call for creating a hardlink.

uint64_t	unlink (const char *path)
	Wrapper for removing a file.

uint64_t	share (char *key, uint64_t size, fd_t fd, clock_t timeout)
	System call for sharing a file descriptor with another process.

uint64_t	sharefile (char key, uint64_t size, const char path, clock_t timeout)
	Helper for sharing a file by its path.

fd_t	claim (const char *key)
	System call for claiming a shared file descriptor.

uint64_t	bind (const char *mountpoint, fd_t source)
	System call for binding a file descriptor to a mountpoint.

uint64_t	mount (const char mountpoint, const char fs, const char *options)
	System call for mounting a filesystem.

uint64_t	unmount (const char *mountpoint)
	System call for unmounting a filesystem.

size_t	readlink (const char path, char buffer, uint64_t count)
	System call for reading the target of a symbolic link.

uint64_t	symlink (const char target, const char linkpath)
	System call for creating a symbolic link.

Macro Definition Documentation

◆ STDIN_FILENO

#define STDIN_FILENO 0

Standard input file descriptor.

Definition at line 35 of file fs.h.

◆ STDOUT_FILENO

#define STDOUT_FILENO 1

Standard output file descriptor.

Definition at line 36 of file fs.h.

◆ STDERR_FILENO

#define STDERR_FILENO 2

Standard error file descriptor.

Definition at line 37 of file fs.h.

◆ PIPE_READ

#define PIPE_READ 0

Pipe read end.

The PIPE_READ constant defines which file descriptor in fd from a open2 call on the /dev/pipe file will be the read end of the pipe.

Definition at line 46 of file fs.h.

◆ PIPE_WRITE

#define PIPE_WRITE 1

Pipe write end.

The PIPE_WRITE constant defines which file descriptor in fd from a open2 call on the /dev/pipe file will be the write end of the pipe.

Definition at line 55 of file fs.h.

◆ F_MAX_SIZE

#define F_MAX_SIZE 512

Maximum buffer size for the F() macro.

Definition at line 60 of file fs.h.

◆ F

#define F	(	format,
		...
	)

Value:

    ({ \
        char* _buffer = alloca(F_MAX_SIZE); \
        int _len = snprintf(_buffer, F_MAX_SIZE, format, __VA_ARGS__); \
        if (_len < 0 || _len >= F_MAX_SIZE) \
        { \
            abort(); \
        } \
        _buffer; \
    })

Allocates a formatted string on the stack.

Warning: Will terminate the program if the size of the formatted string is too large or if an encoding error occurs.

Definition at line 67 of file fs.h.

◆ POLL_SPECIAL

#define POLL_SPECIAL (POLLERR | POLLHUP | POLLNVAL)

Poll event values that will always be checked and included even if not specified.

Definition at line 298 of file fs.h.

◆ KEY_MAX

#define KEY_MAX 128

Maximum size of a key generated by share().

Definition at line 518 of file fs.h.

◆ KEY_128BIT

#define KEY_128BIT 25

The size of a buffer needed to hold a 128-bit key.

Definition at line 520 of file fs.h.

◆ KEY_256BIT

#define KEY_256BIT 45

The size of a buffer needed to hold a 256-bit key.

Definition at line 522 of file fs.h.

◆ KEY_512BIT

#define KEY_512BIT 89

The size of a buffer needed to hold a 512-bit key.

Definition at line 524 of file fs.h.

◆ RETRY_EINTR

#define RETRY_EINTR ( expr )

Value:

    ({ \
        uint64_t _result; \
        do \
        { \
            _result = (expr); \
        } while (_result == ERR && errno == EINTR); \
        _result; \
    })

Macro to automatically retry a function that returns an integer if it errors and errno == EINTR.

Parameters

expr	The expression to evaluate.

Definition at line 613 of file fs.h.

◆ RETRY_EINTR_PTR

#define RETRY_EINTR_PTR ( expr )

Value:

    ({ \
        void* _result; \
        do \
        { \
            _result = (expr); \
        } while (_result == NULL && errno == EINTR); \
        _result; \
    })

Macro to automatically retry a function that returns a pointer if it errors and errno == EINTR.

Parameters

expr	The expression to evaluate.

Definition at line 628 of file fs.h.

Typedef Documentation

◆ seek_origin_t

typedef uint8_t seek_origin_t

Type for the seek() origin argument.

Definition at line 260 of file fs.h.

◆ sbid_t

typedef uint64_t sbid_t

A suberblock identifier that uniquely identifies a superblock within the system.

When combined with a vnode number, this can uniquely identify an vnode within the entire system.

Definition at line 353 of file fs.h.

Enumeration Type Documentation

◆ poll_events_t

enum poll_events_t

Poll events type.

Enumerator
POLLNONE	None.
POLLIN	File descriptor is ready to read.
POLLOUT	File descriptor is ready to write.
POLLERR	File descriptor caused an error.
POLLHUP	Stream socket peer closed connection, or shut down writing of connection.
POLLNVAL	Invalid file descriptor.

Definition at line 285 of file fs.h.

◆ vtype_t

enum vtype_t

Vnode type enum.

Enumerator
VREG	Is a regular file.
VDIR	Is a directory.
VSYMLINK	Is a symbolic link.

Definition at line 341 of file fs.h.

◆ dirent_flags_t

enum dirent_flags_t

Directory entry flags.

Enumerator
DIRENT_NONE
DIRENT_MOUNTED	The directory entry is a mountpoint.

Definition at line 444 of file fs.h.

Function Documentation

◆ open()

fd_t open ( const char * path )

System call for opening files.

The open() function opens a file located at a given path.

Parameters

path	The path to the desired file.

Returns: On success, the file descriptor, on failure returns ERR and errno is set.

Definition at line 8 of file open.c.

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◆ open2()

uint64_t open2	(	const char *	path,
		fd_t	fd[2]
	)

System call for opening 2 file descriptors from one file.

This is intended as a more generic implementation of system calls like pipe() in POSIX systems. One example use case of this system call is pipes, if open2 is called on /dev/pipe then fd[0] will store the read end of the pipe and fd[1] will store the write end of the pipe. But if open() is called on /dev/pipe then the returned file descriptor would be both ends.

Parameters

path	The path to the desired file.
fd	An array of two `fd_t` where the new file descriptors will be stored.

Returns: On success, 0, on failure returns ERR and errno is set.

Definition at line 8 of file open2.c.

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◆ openat()

fd_t openat	(	fd_t	from,
		const char *	path
	)

System call for opening files relative to another file descriptor.

Parameters

from	The file descriptor to open the file relative to, or `FD_NONE` to open from the current working directory.
path	The path to the desired file.

Returns: On success, the file descriptor, on failure returns ERR and errno is set.

Definition at line 8 of file openat.c.

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◆ close()

uint64_t close ( fd_t fd )

System call for closing files.

Parameters

fd	The file descriptor to close.

Returns: On success, 0, on failure returns ERR and errno is set.

Definition at line 8 of file close.c.

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◆ read()

size_t read	(	fd_t	fd,
		void *	buffer,
		size_t	count
	)

System call for reading from files.

Parameters

fd	The file descriptor to read from.
buffer	A pointer to the buffer where the data will be stored.
count	The maximum number of bytes to read.

Returns: On success, the number of bytes read. On end-of-file, 0. On failure, ERR and errno is set.

Definition at line 8 of file read.c.

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◆ reads()

char * reads ( fd_t fd )

Wrapper for reading a file directly into a null-terminated string.

The reads() function reads the entire contents of a file into a newly allocated null-terminated string. The caller is responsible for freeing the returned string.

Parameters

fd	The file descriptor to read from.

Returns: On success, a pointer to the null-terminated string. On failure, NULL and errno is set.

Definition at line 5 of file sread.c.

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◆ readfile()

size_t readfile	(	const char *	path,
		void *	buffer,
		size_t	count,
		size_t	offset
	)

Wrapper for reading a file directly using a path.

Equivalent to calling open(), seek(), read(), and close() in sequence.

Parameters

path	The path to the file.
buffer	A pointer to the buffer where the data will be stored.
count	The maximum number of bytes to read.
offset	The offset in the file to start reading from.

Returns: On success, the number of bytes read. On end-of-file, 0. On failure, ERR and errno is set.

Definition at line 3 of file readfile.c.

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◆ readfiles()

char * readfiles ( const char * path )

Wrapper for reading an entire file directly into a null-terminated string.

The readfiles() function reads the entire contents of a file into a newly allocated null-terminated string. The caller is responsible for freeing the returned string.

Equivalent to calling open(), reads(), and close() in sequence.

Parameters

path	The path to the file.

Returns: On success, a pointer to the null-terminated string. On failure, NULL and errno is set.

Definition at line 3 of file sreadfile.c.

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◆ write()

size_t write	(	fd_t	fd,
		const void *	buffer,
		size_t	count
	)

System call for writing to files.

Parameters

fd	The file descriptor to write to.
buffer	A pointer to the buffer containing the data to write.
count	The number of bytes to write.

Returns: On success, the number of bytes written. On failure, ERR and errno is set.

Definition at line 8 of file write.c.

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◆ writes()

size_t writes	(	fd_t	fd,
		const char *	string
	)

Wrapper for writing a null-terminated string to a file.

Parameters

fd	The file descriptor to write to.
string	The null-terminated string to write.

Returns: On success, the number of bytes written. On failure, ERR and errno is set.

Definition at line 4 of file swrite.c.

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◆ writefile()

size_t writefile	(	const char *	path,
		const void *	buffer,
		size_t	count,
		size_t	offset
	)

Wrapper for writing to a file directly using a path.

Equivalent to calling open(), seek(), write(), and close() in sequence.

Parameters

path	The path to the file.
buffer	A pointer to the buffer containing the data to write.
count	The number of bytes to write.
offset	The offset in the file to start writing to.

Returns: On success, the number of bytes written. On failure, ERR and errno is set.

Definition at line 3 of file writefile.c.

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◆ writefiles()

size_t writefiles	(	const char *	path,
		const char *	string
	)

Wrapper for writing a null-terminated string directly to a file using a path.

Equivalent to calling open(), writes(), and close() in sequence.

Parameters

path	The path to the file.
string	The null-terminated string to write.

Returns: On success, the number of bytes written. On failure, ERR and errno is set.

Definition at line 4 of file swritefile.c.

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◆ scan()

uint64_t scan	(	fd_t	fd,
		const char *	format,
			...
	)

Wrapper for reading from a file descriptor using scan formatting.

Parameters

fd	The file descriptor to read from.
format	The format string.

Returns: On success, the number of input items successfully matched and assigned. On failure, ERR.

Definition at line 6 of file scan.c.

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◆ vscan()

uint64_t vscan	(	fd_t	fd,
		const char *	format,
		va_list	args
	)

Wrapper for reading from a file descriptor using scan formatting with va_list.

Parameters

fd	The file descriptor to read from.
format	The format string.
args	The va_list of arguments.

Returns: On success, the number of input items successfully matched and assigned. On failure, ERR.

Definition at line 29 of file vscan.c.

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◆ scanfile()

uint64_t scanfile	(	const char *	path,
		const char *	format,
			...
	)

Wrapper for reading from a file path using scan formatting.

Equivalent to calling open(), scan(), and close() in sequence.

Parameters

path	The path to the file.
format	The format string.

Returns: On success, the number of input items successfully matched and assigned. On failure, ERR.

Definition at line 6 of file scanfile.c.

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◆ vscanfile()

uint64_t vscanfile	(	const char *	path,
		const char *	format,
		va_list	args
	)

Wrapper for reading from a file path using scan formatting with va_list.

Equivalent to calling open(), vscan(), and close() in sequence.

Parameters

path	The path to the file.
format	The format string.
args	The va_list of arguments.

Returns: On success, the number of input items successfully matched and assigned. On failure, ERR.

Definition at line 6 of file vscanfile.c.

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◆ seek()

size_t seek	(	fd_t	fd,
		ssize_t	offset,
		seek_origin_t	origin
	)

System call for changing the file offset.

Parameters

fd	The file descriptor.
offset	The offset to move the file pointer.
origin	The origin that the offset is relative to (e.g., `SEEK_SET`, `SEEK_CUR`, `SEEK_END`).

Returns: On success, the new offset from the beginning of the file. On failure, ERR and errno is set.

Definition at line 8 of file seek.c.

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◆ chdir()

uint64_t chdir ( const char * path )

System call for changing the cwd.

Parameters

path	The path to the new directory.

Returns: On success, 0. On failure, ERR and errno is set.

Definition at line 8 of file chdir.c.

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◆ poll()

uint64_t poll	(	pollfd_t *	fds,
		uint64_t	amount,
		clock_t	timeout
	)

System call for polling files.

Parameters

fds	An array of `pollfd_t` structures, each specifying a file descriptor to poll in pollfd_t::fd and the events to wait for in pollfd_t::events.
amount	The number of `pollfd_t` structures in the `fds` array.
timeout	The maximum time (in clock ticks) to wait for an event. If `CLOCKS_NEVER`, it waits forever.

Returns: On success, the number of file descriptors for which the events occurred. On timeout, 0. On failure, ERR and errno is set.

Definition at line 8 of file poll.c.

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◆ poll1()

poll_events_t poll1	(	fd_t	fd,
		poll_events_t	events,
		clock_t	timeout
	)

Wrapper for polling one file.

The poll1() function waits for events on a single file descriptor. Otherwise it is identical to poll() and exists simply for convenience.

Parameters

fd	The file descriptor to poll.
events	The events to wait for (e.g., `POLLIN`, `POLLOUT`).
timeout	The maximum time (in clock ticks) to wait for an event. If `CLOCKS_NEVER`, it waits forever.

Returns: On success, the events that occurred. On timeout, 0. On failure, the POLLERR event bit is set and errno is set.

Definition at line 8 of file poll1.c.

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◆ stat()

uint64_t stat	(	const char *	path,
		stat_t *	stat
	)

System call for retrieving info about a file or directory.

Parameters

path	The path to the file or directory.
stat	A pointer to a `stat_t` structure where the file information will be stored.

Returns: On success, 0. On failure, ERR and errno is set.

Definition at line 8 of file stat.c.

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◆ ioctl()

uint64_t ioctl	(	fd_t	fd,
		uint64_t	request,
		void *	argp,
		size_t	size
	)

System call for extended driver behaviour.

The ioctl() function allows drivers to implement unusual behaviour that would be impossible or impractical with a normal file-based API.

Parameters

fd	The file descriptor of the file.
request	The driver-dependent request code.
argp	A pointer to an argument that depends on the request, can be `NULL` if size is 0.
size	The size of the argument pointed to by `argp`.

Returns: On success, the return value depends on the driver but is usually 0. On failure, ERR and errno is set.

Definition at line 8 of file ioctl.c.

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◆ dup()

fd_t dup ( fd_t oldFd )

System call for duplicating file descriptors.

Parameters

oldFd The open file descriptor to duplicate.

Returns: On success, the new file descriptor. On failure, ERR and errno is set.

Definition at line 8 of file dup.c.

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◆ dup2()

fd_t dup2	(	fd_t	oldFd,
		fd_t	newFd
	)

System call for duplicating file descriptors, with a destination.

Parameters

oldFd	The open file descriptor to duplicate.
newFd	The desired new file descriptor.

Returns: On success, the new file descriptor. On failure, ERR and errno is set.

Definition at line 8 of file dup2.c.

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◆ getdents()

size_t getdents	(	fd_t	fd,
		dirent_t *	buffer,
		uint64_t	count
	)

System call for reading directory entires.

Parameters

fd	The file descriptor of the directory to read.
buffer	The destination buffer.
count	The size of the buffer in bytes.

Returns: On success, the total number of bytes written to the buffer. On failure, returns ERR and errno is set.

Definition at line 8 of file getdents.c.

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◆ readdir()

size_t readdir	(	fd_t	fd,
		dirent_t **	buffer,
		uint64_t *	count
	)

Helper for reading all directory entries.

The caller is responsible for freeing the returned pointer.

Parameters

fd	The file descriptor of the directory to read.
buffer	Output pointer to store the allocated buffer containing the directory entries.
count	Output pointer to store the number of bytes written to the buffer.

Returns: On success, 0. On failure, ERR and errno is set.

Definition at line 8 of file readdir.c.

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◆ mkdir()

uint64_t mkdir ( const char * path )

Wrapper for creating a directory.

Parameters

path	The path of the directory to create.

Returns: On success, 0. On failure, ERR and errno is set.

Definition at line 9 of file mkdir.c.

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◆ rmdir()

uint64_t rmdir ( const char * path )

Wrapper for removing a directory.

Parameters

path	The path of the directory to remove.

Returns: On success, 0. On failure, ERR and errno is set.

Definition at line 6 of file rmdir.c.

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◆ link()

uint64_t link	(	const char *	oldPath,
		const char *	newPath
	)

System call for creating a hardlink.

Parameters

oldPath
newPath

Returns: On success, 0. On failure, ERR and errno is set.

Definition at line 8 of file link.c.

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◆ unlink()

uint64_t unlink ( const char * path )

Wrapper for removing a file.

Parameters

path	The path of the file to remove.

Returns: On success, 0. On failure, ERR and errno is set.

Definition at line 5 of file unlink.c.

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◆ share()

uint64_t share	(	char *	key,
		uint64_t	size,
		fd_t	fd,
		clock_t	timeout
	)

System call for sharing a file descriptor with another process.

Parameters

key	Output buffer to store the generated key.
size	The size of the output buffer.
fd	The file descriptor to share.
timeout	The time until the shared file descriptor expires. If `CLOCKS_NEVER`, it never expires.

Returns: On success, 0. On failure, ERR and errno is set.

Definition at line 6 of file share.c.

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◆ sharefile()

uint64_t sharefile	(	char *	key,
		uint64_t	size,
		const char *	path,
		clock_t	timeout
	)

Helper for sharing a file by its path.

Parameters

key	Output buffer to store the generated key.
size	The size of the output buffer.
path	The path to the file to share.
timeout	The time until the shared file descriptor expires. If `CLOCKS_NEVER`, it never expires.

Returns: On success, 0. On failure, ERR and errno is set.

Definition at line 4 of file sharefile.c.

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◆ claim()

fd_t claim ( const char * key )

System call for claiming a shared file descriptor.

After claiming a shared file descriptor, the key is no longer valid and cannot be used again.

Parameters

key	The key identifying the shared file descriptor.

Returns: On success, the claimed file descriptor. On failure, ERR and errno is set.

Definition at line 6 of file claim.c.

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◆ bind()

uint64_t bind	(	const char *	mountpoint,
		fd_t	source
	)

System call for binding a file descriptor to a mountpoint.

The created mount will inherit permissions from the source while the mount behaviour will follow the flags specified in mountpoint.

Parameters

mountpoint	The mountpoint path.
source	The file descriptor to bind, must represent a directory.

Returns: On success, 0. On failure, ERR and errno is set.

Definition at line 5 of file bind.c.

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◆ mount()

uint64_t mount	(	const char *	mountpoint,
		const char *	fs,
		const char *	options
	)

System call for mounting a filesystem.

Parameters

mountpoint	The target path to mount to.
fs	The path to the desired filesystem in the `fs` sysfs directory.
options	A string containing filesystem defined `key=value` pairs, with multiple options separated by commas, or `NULL`.

Returns: On success, 0. On failure, ERR and errno is set.

Definition at line 5 of file mount.c.

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◆ unmount()

uint64_t unmount ( const char * mountpoint )

System call for unmounting a filesystem.

Parameters

mountpoint The target path to unmount.

Returns: On success, 0. On failure, ERR and errno is set.

Definition at line 5 of file unmount.c.

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◆ readlink()

size_t readlink	(	const char *	path,
		char *	buffer,
		uint64_t	count
	)

System call for reading the target of a symbolic link.

Parameters

path	The path to the symbolic link.
buffer	A buffer to store the target path.
count	The size of the buffer.

Returns: On success, the number of bytes read. On failure, ERR and errno is set.

Definition at line 8 of file readlink.c.

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◆ symlink()

uint64_t symlink	(	const char *	target,
		const char *	linkpath
	)

System call for creating a symbolic link.

Parameters

target	The target path of the symbolic link.
linkpath	The path where the symbolic link will be created.

Returns: On success, 0. On failure, ERR and errno is set.

Definition at line 8 of file symlink.c.

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Detailed Description

Data Structures

Macros

Typedefs

Enumerations

Functions

Macro Definition Documentation

◆ STDIN_FILENO

◆ STDOUT_FILENO

◆ STDERR_FILENO

◆ PIPE_READ

◆ PIPE_WRITE

◆ F_MAX_SIZE

◆ F

◆ POLL_SPECIAL

◆ KEY_MAX

◆ KEY_128BIT

◆ KEY_256BIT

◆ KEY_512BIT

◆ RETRY_EINTR

◆ RETRY_EINTR_PTR

Typedef Documentation

◆ seek_origin_t

◆ sbid_t

Enumeration Type Documentation

◆ poll_events_t

◆ vtype_t

◆ dirent_flags_t

Function Documentation

◆ open()

◆ open2()

◆ openat()

◆ close()

◆ read()

◆ reads()

◆ readfile()

◆ readfiles()

◆ write()

◆ writes()

◆ writefile()

◆ writefiles()

◆ scan()

◆ vscan()

◆ scanfile()

◆ vscanfile()

◆ seek()

◆ chdir()

◆ poll()

◆ poll1()

◆ stat()

◆ ioctl()

◆ dup()

◆ dup2()

◆ getdents()

◆ readdir()

◆ mkdir()

◆ rmdir()

◆ link()

◆ unlink()

◆ share()

◆ sharefile()

◆ claim()

◆ bind()

◆ mount()

◆ unmount()

◆ readlink()

◆ symlink()