Reading the Attributes of a File
--------------------------------
To examine the attributes of files, use the functions `stat',
`fstat' and `lstat'. They return the attribute information in a
`struct stat' object. All three functions are declared in the header
file `sys/stat.h'.
- Function: int stat (const char *FILENAME, struct stat *BUF)
The `stat' function returns information about the attributes of the
file named by FILENAME in the structure pointed to by BUF.
If FILENAME is the name of a symbolic link, the attributes you get
describe the file that the link points to. If the link points to a
nonexistent file name, then `stat' fails reporting a nonexistent
file.
The return value is `0' if the operation is successful, or `-1' on
failure. In addition to the usual file name errors (Note:File
Name Errors, the following `errno' error conditions are defined
for this function:
`ENOENT'
The file named by FILENAME doesn't exist.
When the sources are compiled with `_FILE_OFFSET_BITS == 64' this
function is in fact `stat64' since the LFS interface transparently
replaces the normal implementation.
- Function: int stat64 (const char *FILENAME, struct stat64 *BUF)
This function is similar to `stat' but it is also able to work on
files larger then 2^31 bytes on 32-bit systems. To be able to do
this the result is stored in a variable of type `struct stat64' to
which BUF must point.
When the sources are compiled with `_FILE_OFFSET_BITS == 64' this
function is available under the name `stat' and so transparently
replaces the interface for small files on 32-bit machines.
- Function: int fstat (int FILEDES, struct stat *BUF)
The `fstat' function is like `stat', except that it takes an open
file descriptor as an argument instead of a file name. Note:Low-Level I/O.
Like `stat', `fstat' returns `0' on success and `-1' on failure.
The following `errno' error conditions are defined for `fstat':
`EBADF'
The FILEDES argument is not a valid file descriptor.
When the sources are compiled with `_FILE_OFFSET_BITS == 64' this
function is in fact `fstat64' since the LFS interface transparently
replaces the normal implementation.
- Function: int fstat64 (int FILEDES, struct stat64 *BUF)
This function is similar to `fstat' but is able to work on large
files on 32-bit platforms. For large files the file descriptor
FILEDES should be obtained by `open64' or `creat64'. The BUF
pointer points to a variable of type `struct stat64' which is able
to represent the larger values.
When the sources are compiled with `_FILE_OFFSET_BITS == 64' this
function is available under the name `fstat' and so transparently
replaces the interface for small files on 32-bit machines.
- Function: int lstat (const char *FILENAME, struct stat *BUF)
The `lstat' function is like `stat', except that it does not
follow symbolic links. If FILENAME is the name of a symbolic
link, `lstat' returns information about the link itself; otherwise
`lstat' works like `stat'. Note:Symbolic Links.
When the sources are compiled with `_FILE_OFFSET_BITS == 64' this
function is in fact `lstat64' since the LFS interface transparently
replaces the normal implementation.
- Function: int lstat64 (const char *FILENAME, struct stat64 *BUF)
This function is similar to `lstat' but it is also able to work on
files larger then 2^31 bytes on 32-bit systems. To be able to do
this the result is stored in a variable of type `struct stat64' to
which BUF must point.
When the sources are compiled with `_FILE_OFFSET_BITS == 64' this
function is available under the name `lstat' and so transparently
replaces the interface for small files on 32-bit machines.