NAME
readlink() — read the contents of a symbolic link
SYNOPSIS
#include <symlink.h>
int readlink(
const char *path,
char *buf,
size_t bufsiz
);
DESCRIPTION
The
readlink()
function places the contents of the
symbolic link referred to by path in the buffer
buf
which has size
bufsiz.
If the number of bytes in
the symbolic link is less than
bufsiz,
the contents of the remainder of
buf
are unspecified.
In systems conforming to AES standards, the returned
string will be null-terminated if the length of the path
name string is less than
bufsiz.
If the length of the path name string is exactly
bufsiz,
the string will not be null-terminated when returned.
If the length of the path name string exceeds
bufsiz,
the
readlink()
function returns
-1
and sets
errno
to
ERANGE.
Note
The kernel tunable parameter
hpux_aes_override
can be queried to determine whether a system conforms to AES standards.
RETURN VALUE
Upon successful completion,
readlink()
returns the count of bytes placed in the buffer.
Otherwise, it returns a value of
-1,
leaves the buffer unchanged, and sets
errno
to indicate the error.
ERRORS
The
readlink()
function will fail if:
- [EACCES]
Search permission is denied for a component of the path prefix.
- [EACCES]
Read permission is denied for the directory.
- [EFAULT]
buf
or
path
points outside the process's allocated address space.
Reliable detection of this error is implementation-dependent.
- [EINVAL]
The path argument names a file that is not a symbolic link.
- [EIO]
An I/O error occurred while reading from the file system.
- [ELOOP]
Too many symbolic links were encountered in resolving path.
- [ENAMETOOLONG]
The length of path exceeds
PATH_MAX,
or a pathname component is longer than
NAME_MAX.
In systems conforming to AES standards, this error will be
returned when the path exceeds the
PATH_MAX
bytes or a pathname component exceeds the
NAME_MAX
bytes while
_POSIX_NO_TRUNC
is in effect.
- [ENAMETOOLONG]
Pathname resolution of a symbolic link produced an
intermediate result whose length exceeds
PATH_MAX.
- [ENOENT]
A component of path does not name an existing file or path is
an empty string.
- [ENOTDIR]
A component of the path prefix is not a directory.
- [ERANGE]
The length of the
path
name string read from the symbolic link exceeds
bufsiz.
AUTHOR
readlink()
was developed by the University of California, Berkeley.
STANDARDS CONFORMANCE
readlink() : AES, SVID3