Originální popis anglicky:
lstat - get symbolic link status
Návod, kniha: POSIX Programmer's Manual
#include <sys/stat.h>
int lstat(const char *restrict
path, struct stat
*restrict buf);
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.
Upon successful completion,
lstat() shall return 0. Otherwise, it shall
return -1 and set
errno to indicate the error.
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.
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);
None.
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.
None.
fstat() ,
readlink() ,
stat() ,
symlink() , the Base
Definitions volume of IEEE Std 1003.1-2001,
<sys/stat.h>
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
.
