\input texinfo @c -*-texinfo-*-
@c %**start of header
@setfilename libext2fs.info
-@settitle The EXT2FS Library (version 1.37)
+@settitle The EXT2FS Library (version 1.41.12)
@synindex tp fn
@comment %**end of header
@ifinfo
@dircategory Development
-@format
-START-INFO-DIR-ENTRY
-* libext2fs: (libext2fs.info). The EXT2FS library.
-END-INFO-DIR-ENTRY
-@end format
+@direntry
+* libext2fs: (libext2fs). The EXT2FS library.
+@end direntry
@end ifinfo
@c smallbook
This file documents the ext2fs library, a library for manipulating the
ext2 filesystem.
-Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005 Theodore Ts'o
+Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
+2006, 2007, 2008, 2009 by Theodore Ts'o
Permission is granted to make and distribute verbatim copies of
this manual provided the copyright notice and this permission notice
@title The EXT2FS Library
@subtitle The EXT2FS Library
-@subtitle Version 1.37
-@subtitle January 2005
+@subtitle Version 1.41.12
+@subtitle May 2010
@author by Theodore Ts'o
@top The EXT2FS Library
-This manual documents the EXT2FS Library, version 1.37.
+This manual documents the EXT2FS Library, version 1.41.12.
@end ifinfo
@menu
* Filesystem-level functions::
+* File I/O Functions::
* Inode Functions::
* Directory functions::
* Bitmap Functions::
@c ----------------------------------------------------------------------
-@node Filesystem-level functions, Inode Functions, EXT2FS Library Functions, EXT2FS Library Functions
+@node Filesystem-level functions, File I/O Functions, EXT2FS Library Functions, EXT2FS Library Functions
@comment node-name, next, previous, up
@section Filesystem-level functions
to be written when the filesystem is closed or flushed.
@end deftypefun
+@c ----------------------------------------------------------------------
+
+@node File I/O Functions, Inode Functions, Filesystem-level functions, EXT2FS Library Functions
+@comment node-name, next, previous, up
+@section File I/O Functions
+
+The following functions provide a convenient abstraction to read or
+write a file in an filesystem. The interface is similar in spirit to
+the Linux/POSIX file I/O system calls.
+
+@menu
+* File handle manipulation::
+* Reading and writing data::
+* Changing the file offset ::
+* Getting the file size::
+@end menu
+
+@c ----------------------------------------------------------------------
+
+@node File handle manipulation, Reading and writing data, File I/O Functions, File I/O Functions
+@comment node-name, next, previous, up
+@subsection File handle manipulation
+
+The file handle functions much like a file descriptor in the Linux/POSIX
+file I/O system calls. Unlike the Linux/POSIX system calls, files are
+opened via inode numbers instead of via pathnames. To resolve a
+pathname to an inode number, use the function @code{ext2fs_namei} or to
+create a new file, use @code{ext2fs_new_inode} and @code{ext2fs_link}.
+
+@deftypefun errcode_t ext2fs_file_open2 (ext2_filsys @var{fs}, ext2_ino_t @var{ino}, struct ext2_inode *@var{inode}, int @var{flags}, ext2_file_t *@var{ret})
+@deftypefunx errcode_t ext2fs_file_open (ext2_filsys @var{fs}, ext2_ino_t @var{ino}, int @var{flags}, ext2_file_t *@var{ret})
+
+Opens a file identified by inode number @var{ino} in filesystem @var{fs}
+and returns a file handle in @var{ret}. If an inode structure is
+provided in @var{inode}, then it is used instead of reading the inode
+from the filesystem.
+
+The @var{flags} argument contains a bitmask of flags which control how
+the file should be opened.
+
+@table @code
+@item EXT2_FILE_WRITE
+Open the file for reading and writing. Without this flag, the file is
+opened for writing only.
+
+@item EXT2_FILE_CREATE
+Create the file if it is not already present.
+
+@end table
+@end deftypefun
+
+@deftypefun ext2_filsys ext2fs_file_get_fs (ext2_file_t @var{file})
+Return the filesystem handle where the open file @var{file} was opened.
+@end deftypefun
+
+@deftypefun errcode_t ext2fs_file_close (ext2_file_t @var{file})
+Close the file handle @var{file}.
+@end deftypefun
+
+@deftypefun errcode_t ext2fs_file_flush (ext2_file_t @var{file})
+Force any data written via @code{ext2fs_file_write} to disk.
+@end deftypefun
+@c ----------------------------------------------------------------------
+
+@node Reading and writing data, Changing the file offset , File handle manipulation, File I/O Functions
+@comment node-name, next, previous, up
+@subsection Reading and writing data
+
+@deftypefun errcode_t ext2fs_file_read (ext2_file_t @var{file}, void *@var{buf}, unsigned int @var{wanted}, unsigned int *@var{got})
+Read @var{wanted} bytes of data from @var{file} store it in the buffer
+@var{buf}. The number of bytes that was actually read is returned
+via @var{got}.
+@end deftypefun
+
+@deftypefun errcode_t ext2fs_file_write (ext2_file_t @var{file}, const void *@var{buf}, unsigned int @var{nbytes}, unsigned int *@var{written})
+Write @var{wanted} bytes of data from the buffer @var{buf} to the
+current file position of @var{file}. The number of bytes that was
+actually written is returned via @var{got}.
+@end deftypefun
+
+@c ----------------------------------------------------------------------
+
+@node Changing the file offset , Getting the file size, Reading and writing data, File I/O Functions
+@comment node-name, next, previous, up
+@subsection Changing the file offset
+
+@deftypefun errcode_t ext2fs_file_llseek (ext2_file_t @var{file}, __u64 @var{offset}, int @var{whence}, __u64 *@var{ret_pos})
+@deftypefunx errcode_t ext2fs_file_lseek (ext2_file_t @var{file}, ext2_off_t @var{offset}, int @var{whence}, ext2_off_t *@var{ret_pos})
+Change the current file position of @var{file} according to the
+directive @var{whence} as follows:
+
+@table @code
+@item EXT2_SEEK_SET
+The file position is set to @var{offset} bytes from the beginning of the
+file.
+
+@item EXT2_SEEK_CUR
+The file position set to its current location plus @var{offset} bytes.
+
+@item EXT2_SEEK_END
+The file position is set to the size of the file plus @var{offset}
+bytes.
+@end table
+
+The current offset is returned via @var{ret_pos}.
+@end deftypefun
+
+@c ----------------------------------------------------------------------
+
+@node Getting the file size, , Changing the file offset , File I/O Functions
+@comment node-name, next, previous, up
+@subsection Getting the file size
+
+@deftypefun errcode_t ext2fs_file_get_lsize (ext2_file_t @var{file}, __u64 *@var{ret_size})
+Return the size of the file @var{file} in @var{ret_size}.
+@end deftypefun
+
+@deftypefun ext2_off_t ext2fs_file_get_size (ext2_file_t @var{file})
+Return the size of the file @var{file}.
+@end deftypefun
@c ----------------------------------------------------------------------
-@node Inode Functions, Directory functions, Filesystem-level functions, EXT2FS Library Functions
+@node Inode Functions, Directory functions, File I/O Functions, EXT2FS Library Functions
@comment node-name, next, previous, up
@section Inode Functions
@comment node-name, next, previous, up
@subsection Iterating over blocks in an inode
-@deftypefun errcode_t ext2fs_block_iterate (ext2_filsys @var{fs},
-ext2_ino_t @var{ino}, int @var{flags}, char *block_buf, int
-(*func)(ext2_filsys @var{fs}, blk_t *@var{blocknr}, int @var{blockcnt},
-void *@var{private}), void *@var{private})
+@deftypefun errcode_t ext2fs_block_iterate (ext2_filsys @var{fs}, ext2_ino_t @var{ino}, int @var{flags}, char *block_buf, int (*func)(ext2_filsys @var{fs}, blk_t *@var{blocknr}, int @var{blockcnt}, void *@var{private}), void *@var{private})
Iterate over all of the blocks in inode number @var{ino} in filesystem
@var{fs}, by calling the function @var{func} for each block in the
also known as BLOCK_FLAG_APPEND, since it is also used by functions
such as ext2fs_expand_dir() to add a new block to an inode.
-@item BLOCK_FLAG_TRAVERSE
+@item BLOCK_FLAG_DEPTH_TRAVERSE
This flag indicates that the iterator function for the
indirect, doubly indirect, etc. blocks should be called after all
of the blocks containined in the indirect blocks are processed.
@deftypefun errcode_t ext2fs_block_iterate2 (ext2_filsys @var{fs}, ext2_ino_t @var{ino}, int @var{flags}, char *@var{block}_buf, int (*func)(ext2_filsys @var{fs}, blk_t *@var{blocknr}, e2_blkcnt_t @var{blockcnt}, blk_t @var{ref_blk}, int @var{ref_offset}, void *@var{private}), void *@var{private})
-This function is much like @code{ext2fs_block_iterate2}, except that the
+This function is much like @code{ext2fs_block_iterate}, except that the
@var{blockcnt} type is a 64-bit signed quantity, to support larger
files, and the addition of the @var{ref_blk} and @var{ref_offset}
arguments passed to the callback function, which identify the location
Returns 0 if @var{ino} is a directory, and @code{ENOTDIR} if it is not.
@end deftypefun
-@deftypefun int ext2_inode_has_valid_blocks (struct ext2_inode *@var{inode})
+@deftypefun int ext2fs_inode_has_valid_blocks (struct ext2_inode *@var{inode})
Returns 1 if the inode's block entries actually valid block entries, and
0 if not. Inodes which represent devices and fast symbolic links do not
byte swapping if necessary.
@end deftypefun
-@deftypefun errcode_t ext2fs_new_dir_block (ext2_filsys @var{fs},
-ext2_ino_t @var{dir_ino}, ext2_ino_t @var{parent_ino}, char
-**@var{block})
+@deftypefun errcode_t ext2fs_new_dir_block (ext2_filsys @var{fs}, ext2_ino_t @var{dir_ino}, ext2_ino_t @var{parent_ino}, char **@var{block})
This function creates a new directory block in @var{block}. If
@var{dir_ino} is non-zero, then @var{dir_info} and @var{parent_ino} is used
@deftypefun errcode_t ext2fs_check_desc (ext2_filsys @var{fs})
@end deftypefun
-@deftypefun errcode_t ext2_get_num_dirs (ext2_filsys @var{fs}, ext2_ino_t *@var{ret_num_dirs})
+@deftypefun errcode_t ext2fs_get_num_dirs (ext2_filsys @var{fs}, ext2_ino_t *@var{ret_num_dirs})
@end deftypefun
projects / thirdparty / e2fsprogs.git / blobdiff