Reading and Writing

Reading and Writing —

Synopsis




enum        GnomeVFSSeekPosition;
GnomeVFSResult gnome_vfs_read               (GnomeVFSHandle *handle,
                                             gpointer buffer,
                                             GnomeVFSFileSize bytes,
                                             GnomeVFSFileSize *bytes_read);
GnomeVFSResult gnome_vfs_write              (GnomeVFSHandle *handle,
                                             gconstpointer buffer,
                                             GnomeVFSFileSize bytes,
                                             GnomeVFSFileSize *bytes_written);
GnomeVFSResult gnome_vfs_seek               (GnomeVFSHandle *handle,
                                             GnomeVFSSeekPosition whence,
                                             GnomeVFSFileOffset offset);
GnomeVFSResult gnome_vfs_tell               (GnomeVFSHandle *handle,
                                             GnomeVFSFileSize *offset_return);

Description

Reading and writing operations are explained, also gnome_vfs_seek, which is used to move the file pointer inside the file.

Details

enum GnomeVFSSeekPosition

typedef enum {
        GNOME_VFS_SEEK_START,
        GNOME_VFS_SEEK_CURRENT,
        GNOME_VFS_SEEK_END
} GnomeVFSSeekPosition;

This is used to specify the start position for seek operations.

`GNOME_VFS_SEEK_START`	Start of the file.
`GNOME_VFS_SEEK_CURRENT`	Current position.
`GNOME_VFS_SEEK_END`	End of the file.

gnome_vfs_read ()

GnomeVFSResult gnome_vfs_read               (GnomeVFSHandle *handle,
                                             gpointer buffer,
                                             GnomeVFSFileSize bytes,
                                             GnomeVFSFileSize *bytes_read);

Read bytes from handle. As with Unix system calls, the number of bytes read can effectively be less than bytes on return and will be stored in bytes_read.

`handle` :	Handle of the file to read data from
`buffer` :	Pointer to a buffer that must be at least `bytes` bytes large
`bytes` :	Number of bytes to read
`bytes_read` :	Pointer to a variable that will hold the number of bytes effectively read on return.
Returns :	An integer representing the result of the operation

gnome_vfs_write ()

GnomeVFSResult gnome_vfs_write              (GnomeVFSHandle *handle,
                                             gconstpointer buffer,
                                             GnomeVFSFileSize bytes,
                                             GnomeVFSFileSize *bytes_written);

Write bytes into the file opened through handle. As with Unix system calls, the number of bytes written can effectively be less than bytes on return and will be stored in bytes_written.

`handle` :	Handle of the file to write data to
`buffer` :	Pointer to the buffer containing the data to be written
`bytes` :	Number of bytes to write
`bytes_written` :	Pointer to a variable that will hold the number of bytes effectively written on return.
Returns :	An integer representing the result of the operation

gnome_vfs_seek ()

GnomeVFSResult gnome_vfs_seek               (GnomeVFSHandle *handle,
                                             GnomeVFSSeekPosition whence,
                                             GnomeVFSFileOffset offset);

Set the current position for reading/writing through handle.

`handle` :	Handle for which the current position must be changed
`whence` :	Integer value representing the starting position
`offset` :	Number of bytes to skip from the position specified by `whence` (a positive value means to move forward; a negative one to move backwards)
Returns :

gnome_vfs_tell ()

GnomeVFSResult gnome_vfs_tell               (GnomeVFSHandle *handle,
                                             GnomeVFSFileSize *offset_return);

Return the current position on handle. This is the point in the file pointed to by handle that reads and writes will occur on.

`handle` :	Handle for which the current position must be retrieved
`offset_return` :	Pointer to a variable that will contain the current position on return
Returns :	An integer representing the result of the operation