xref: /freebsd/lib/libsys/fhreadlink.2 (revision 8269e7673cf033aba67dab8264fe719920c70f87)

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.Dd November 30, 2022
.Dt FHREADLINK 2
.Os
.Sh NAME
.Nm fhreadlink
.Nd read value of a symbolic link
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In sys/param.h
.In sys/mount.h
.Ft int
.Fn fhreadlink "fhandle_t *fhp" "char *buf" "size_t bufsize"
.Fc
.Sh DESCRIPTION
The
.Fn fhreadlink
system call
places the contents of the symbolic link
.Fa fhp
in the buffer
.Fa buf ,
which has size
.Fa bufsiz .
The
.Fn fhreadlink
system call does not append a
.Dv NUL
character to
.Fa buf .
.Pp
.Sh RETURN VALUES
The call returns the count of characters placed in the buffer
if it succeeds, or a \-1 if an error occurs, placing the error
code in the global variable
.Va errno .
.Sh ERRORS
The
.Fn readlink
system call
will fail if:
.Bl -tag -width Er
.It Bq Er ENOENT
The named file does not exist.
.It Bq Er ELOOP
Too many symbolic links were encountered in translating the file handle
.Fa fhp .
.It Bq Er EINVAL
The named file is not a symbolic link.
.It Bq Er EIO
An I/O error occurred while reading from the file system.
.It Bq Er EINTEGRITY
Corrupted data was detected while reading from the file system.
.It Bq Er EFAULT
The
.Fa buf
argument
extends outside the process's allocated address space.
.It Bq Er ESTALE
The file handle
.Fa fhp
is no longer valid
.El
.El
.Sh SEE ALSO
.Xr fhstat 2 ,
.Xr fhlink 2 ,
.Sh HISTORY
The
.Fn fhreadlink
system call first appeared in
.Fx 12.1 .