LSTAT
Section: POSIX Programmer's Manual (3P)
Updated: 2003
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PROLOG
This manual page is part of the POSIX Programmer's Manual.
The Linux implementation of this interface may differ (consult
the corresponding Linux manual page for details of Linux behavior),
or the interface may not be implemented on Linux.
NAME
lstat - get symbolic link status
SYNOPSIS
#include <sys/stat.h>
int lstat(const char *restrict path, struct stat *restrict
buf);
DESCRIPTION
The lstat() function shall be equivalent to stat(), except
when path
refers to a symbolic link. In that case lstat() shall return
information about the link, while stat() shall return information
about the file the link references.
For symbolic links, the st_mode member shall contain meaningful
information when used with the file type macros, and the
st_size member shall contain the length of the pathname contained
in the symbolic link. File mode bits and the contents of
the remaining members of the stat structure are unspecified.
The value returned in the st_size member is the length
of the contents of the symbolic link, and does not count any trailing
null.
RETURN VALUE
Upon successful completion, lstat() shall return 0. Otherwise,
it shall return -1 and set errno to indicate the
error.
ERRORS
The lstat() function shall fail if:
- EACCES
-
A component of the path prefix denies search permission.
- EIO
-
An error occurred while reading from the file system.
- ELOOP
-
A loop exists in symbolic links encountered during resolution of the
path argument.
- ENAMETOOLONG
-
The length of a pathname exceeds {PATH_MAX} or a pathname component
is longer than {NAME_MAX}.
- ENOTDIR
-
A component of the path prefix is not a directory.
- ENOENT
-
A component of path does not name an existing file or path
is an empty string.
- EOVERFLOW
-
The file size in bytes or the number of blocks allocated to the file
or the file serial number cannot be represented correctly
in the structure pointed to by buf.
The lstat() function may fail if:
- ELOOP
-
More than {SYMLOOP_MAX} symbolic links were encountered during resolution
of the path argument.
- ENAMETOOLONG
-
As a result of encountering a symbolic link in resolution of the path
argument, the length of the substituted pathname
string exceeded {PATH_MAX}.
- EOVERFLOW
-
One of the members is too large to store into the structure pointed
to by the buf argument.
The following sections are informative.
EXAMPLES
Obtaining Symbolic Link Status Information
The following example shows how to obtain status information for a
symbolic link named /modules/pass1. The structure
variable buffer is defined for the stat structure. If
the path argument specified the filename for the file
pointed to by the symbolic link ( /home/cnd/mod1), the results
of calling the function would be the same as those returned
by a call to the stat() function.
-
#include <sys/stat.h>
struct stat buffer;
int status;
...
status = lstat("/modules/pass1", &buffer);
APPLICATION USAGE
None.
RATIONALE
The lstat() function is not required to update the time-related
fields if the named file is not a symbolic link. While
the st_uid, st_gid, st_atime, st_mtime, and
st_ctime members of the stat structure may
apply to a symbolic link, they are not required to do so. No functions
in IEEE Std 1003.1-2001 are required to maintain
any of these time fields.
FUTURE DIRECTIONS
None.
SEE ALSO
fstat(), readlink(), stat(),
symlink(), the Base Definitions volume of IEEE Std 1003.1-2001,
<sys/stat.h>
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group. In the
event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be obtained online at
http://www.opengroup.org/unix/online.html .