xref: /freebsd/lib/libsys/fhreadlink.2 (revision 3f0efe05432b1633991114ca4ca330102a561959)
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26.Dd November 30, 2022
27.Dt FHREADLINK 2
28.Os
29.Sh NAME
30.Nm fhreadlink
31.Nd read value of a symbolic link
32.Sh LIBRARY
33.Lb libc
34.Sh SYNOPSIS
35.In sys/param.h
36.In sys/mount.h
37.Ft int
38.Fn fhreadlink "fhandle_t *fhp" "char *buf" "size_t bufsize"
39.Fc
40.Sh DESCRIPTION
41The
42.Fn fhreadlink
43system call
44places the contents of the symbolic link
45.Fa fhp
46in the buffer
47.Fa buf ,
48which has size
49.Fa bufsiz .
50The
51.Fn fhreadlink
52system call does not append a
53.Dv NUL
54character to
55.Fa buf .
56.Pp
57.Sh RETURN VALUES
58The call returns the count of characters placed in the buffer
59if it succeeds, or a \-1 if an error occurs, placing the error
60code in the global variable
61.Va errno .
62.Sh ERRORS
63The
64.Fn readlink
65system call
66will fail if:
67.Bl -tag -width Er
68.It Bq Er ENOENT
69The named file does not exist.
70.It Bq Er ELOOP
71Too many symbolic links were encountered in translating the file handle
72.Fa fhp .
73.It Bq Er EINVAL
74The named file is not a symbolic link.
75.It Bq Er EIO
76An I/O error occurred while reading from the file system.
77.It Bq Er EINTEGRITY
78Corrupted data was detected while reading from the file system.
79.It Bq Er EFAULT
80The
81.Fa buf
82argument
83extends outside the process's allocated address space.
84.It Bq Er ESTALE
85The file handle
86.Fa fhp
87is no longer valid
88.El
89.El
90.Sh SEE ALSO
91.Xr fhstat 2 ,
92.Xr fhlink 2 ,
93.Sh HISTORY
94The
95.Fn fhreadlink
96system call first appeared in
97.Fx 12.1 .
98