xref: /netbsd-src/lib/libc/sys/readlink.2 (revision 5f7096188587a2c7c95fa3c69b78e1ec9c7923d0)
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32.\"     from: @(#)readlink.2	6.8 (Berkeley) 3/10/91
33.\"	$Id: readlink.2,v 1.3 1993/11/25 00:39:27 jtc Exp $
34.\"
35.Dd March 10, 1991
36.Dt READLINK 2
37.Os BSD 4.2
38.Sh NAME
39.Nm readlink
40.Nd read value of a symbolic link
41.Sh SYNOPSIS
42.Fd #include <unistd.h>
43.Ft int
44.Fn readlink "const char *path" "char *buf" "int bufsiz"
45.Sh DESCRIPTION
46.Fn Readlink
47places the contents of the symbolic link
48.Fa path
49in the buffer
50.Fa buf ,
51which has size
52.Fa bufsiz .
53.Nm Readlink
54does not append a
55.Dv NUL
56character to
57.Fa buf .
58.Sh RETURN VALUES
59The call returns the count of characters placed in the buffer
60if it succeeds, or a -1 if an error occurs, placing the error
61code in the global variable
62.Va errno .
63.Sh ERRORS
64.Fn Readlink
65will fail if:
66.Bl -tag -width ENAMETOOLONG
67.It Bq Er ENOTDIR
68A component of the path prefix is not a directory.
69.It Bq Er EINVAL
70The pathname contains a character with the high-order bit set.
71.It Bq Er ENAMETOOLONG
72A component of a pathname exceeded 255 characters,
73or an entire path name exceeded 1023 characters.
74.It Bq Er ENOENT
75The named file does not exist.
76.It Bq Er EACCES
77Search permission is denied for a component of the path prefix.
78.It Bq Er ELOOP
79Too many symbolic links were encountered in translating the pathname.
80.It Bq Er EINVAL
81The named file is not a symbolic link.
82.It Bq Er EIO
83An I/O error occurred while reading from the file system.
84.It Bq Er EFAULT
85.Fa Buf
86extends outside the process's allocated address space.
87.El
88.Sh SEE ALSO
89.Xr stat 2 ,
90.Xr lstat 2 ,
91.Xr symlink 2
92.Sh HISTORY
93The
94.Fn readlink
95function call appeared in
96.Bx 4.2 .
97