xref: /dragonfly/lib/libc/sys/readlink.2 (revision 6b5c5d0d)
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32.\"     @(#)readlink.2	8.1 (Berkeley) 6/4/93
33.\" $FreeBSD: src/lib/libc/sys/readlink.2,v 1.7.2.4 2001/12/14 18:34:01 ru Exp $
34.\" $DragonFly: src/lib/libc/sys/readlink.2,v 1.2 2003/06/17 04:26:47 dillon Exp $
35.\"
36.Dd June 4, 1993
37.Dt READLINK 2
38.Os
39.Sh NAME
40.Nm readlink
41.Nd read value of a symbolic link
42.Sh LIBRARY
43.Lb libc
44.Sh SYNOPSIS
45.In unistd.h
46.Ft int
47.Fn readlink "const char *path" "char *buf" "int bufsiz"
48.Sh DESCRIPTION
49.Fn Readlink
50places the contents of the symbolic link
51.Fa path
52in the buffer
53.Fa buf ,
54which has size
55.Fa bufsiz .
56The
57.Fn readlink
58function does not append a
59.Dv NUL
60character to
61.Fa buf .
62.Sh RETURN VALUES
63The call returns the count of characters placed in the buffer
64if it succeeds, or a -1 if an error occurs, placing the error
65code in the global variable
66.Va errno .
67.Sh ERRORS
68.Fn Readlink
69will fail if:
70.Bl -tag -width Er
71.It Bq Er ENOTDIR
72A component of the path prefix is not a directory.
73.It Bq Er ENAMETOOLONG
74A component of a pathname exceeded 255 characters,
75or an entire path name exceeded 1023 characters.
76.It Bq Er ENOENT
77The named file does not exist.
78.It Bq Er EACCES
79Search permission is denied for a component of the path prefix.
80.It Bq Er ELOOP
81Too many symbolic links were encountered in translating the pathname.
82.It Bq Er EINVAL
83The named file is not a symbolic link.
84.It Bq Er EIO
85An I/O error occurred while reading from the file system.
86.It Bq Er EFAULT
87.Fa Buf
88extends outside the process's allocated address space.
89.El
90.Sh SEE ALSO
91.Xr lstat 2 ,
92.Xr stat 2 ,
93.Xr symlink 2 ,
94.Xr symlink 7
95.Sh HISTORY
96The
97.Fn readlink
98function call appeared in
99.Bx 4.2 .
100