xref: /netbsd-src/lib/libc/sys/readlink.2 (revision ae9172d6cd9432a6a1a56760d86b32c57a66c39c)
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32.\"     from: @(#)readlink.2	6.8 (Berkeley) 3/10/91
33.\"	$Id: readlink.2,v 1.6 1994/04/22 00:13:44 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 Er
67.It Bq Er ENOTDIR
68A component of the path prefix is not a directory.
69.It Bq Er ENAMETOOLONG
70A component of a pathname exceeded
71.Dv {NAME_MAX}
72characters, or an entire path name exceeded
73.Dv {PATH_MAX}
74characters.
75.It Bq Er ENOENT
76The named file does not exist.
77.It Bq Er EACCES
78Search permission is denied for a component of the path prefix.
79.It Bq Er ELOOP
80Too many symbolic links were encountered in translating the pathname.
81.It Bq Er EINVAL
82The named file is not a symbolic link.
83.It Bq Er EIO
84An I/O error occurred while reading from the file system.
85.It Bq Er EFAULT
86.Fa Buf
87extends outside the process's allocated address space.
88.El
89.Sh SEE ALSO
90.Xr stat 2 ,
91.Xr lstat 2 ,
92.Xr symlink 2
93.Sh HISTORY
94The
95.Fn readlink
96function call appeared in
97.Bx 4.2 .
98