getfh.2

早期freebsd实现

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.\"	@(#)getfh.2	8.1 (Berkeley) 6/9/93
.\"
.Dd June 9, 1993
.Dt GETFH 2
.Os
.Sh NAME
.Nm getfh
.Nd get file handle
.Sh SYNOPSIS
.Fd #include <sys/types.h>
.Fd #include <sys/mount.h>
.Ft int
.Fn getfh "char *path" "fhandle_t *fhp"
.Sh DESCRIPTION
.Fn Getfh
returns a file handle for the specified file or directory
in the file handle pointed to by
.Fa fhp .
This system call is restricted to the superuser.
.Sh RETURN VALUES
Upon successful completion, a value of 0 is returned.
Otherwise, -1 is returned and the global variable
.Va errno
is set to indicate the error.
.Sh ERRORS
.Fn Getfh
fails if one or more of the following are true:
.Bl -tag -width Er
.It Bq ENOTDIR
A component of the path prefix of
.Fa path
is not a directory.
.It Bq EINVAL
.Fa path
contains a character with the high-order bit set.
.It Bq ENAMETOOLONG
The length of a component of
.Fa path
exceeds 255 characters,
or the length of
.Fa path
exceeds 1023 characters.
.It Bq ENOENT
The file referred to by
.Fa path
does not exist.
.It Bq EACCES
Search permission is denied for a component of the path prefix of
.Fa path .
.It Bq ELOOP
Too many symbolic links were encountered in translating
.Fa path .
.It Bq EFAULT
.Fa Fhp
points to an invalid address.
.It Bq EIO
An
.Tn I/O
error occurred while reading from or writing to the file system.
.El
.Sh HISTORY
The
.Nm getfh
function
first appeared in 4.4BSD.