File: libc.info, Node: Reading Attributes, Next: Testing File Type, Prev: Attribute Meanings, Up: File Attributes
14.9.2 Reading the Attributes of a File
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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)
Preliminary: | MT-Safe | AS-Safe | AC-Safe | *Note POSIX Safety
Concepts::.
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)
Preliminary: | MT-Safe | AS-Safe | AC-Safe | *Note POSIX Safety
Concepts::.
This function is similar to 'stat' but it is also able to work on
files larger than 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)
Preliminary: | MT-Safe | AS-Safe | AC-Safe | *Note POSIX Safety
Concepts::.
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)
Preliminary: | MT-Safe | AS-Safe | AC-Safe | *Note POSIX Safety
Concepts::.
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)
Preliminary: | MT-Safe | AS-Safe | AC-Safe | *Note POSIX Safety
Concepts::.
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)
Preliminary: | MT-Safe | AS-Safe | AC-Safe | *Note POSIX Safety
Concepts::.
This function is similar to 'lstat' but it is also able to work on
files larger than 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.