FHOPEN(2)

NAME
fhopen, fhstat, fhstatfs, fhstatvfs - access file via file handle

LIBRARY
libc

SYNOPSIS
#include <sys/param.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/statvfs.h>
int
fhopen(const fhandle_t *fhp, int flags);
int
fhstat(const fhandle_t *fhp, struct stat *sb);
int
fhstatfs(const fhandle_t *fhp, struct statfs *buf);
int
fhstatvfs(const fhandle_t *fhp, struct statvfs *buf);

DESCRIPTION
These functions provide a means to access a file given the file handle fhp. As this method bypasses directory access restrictions, these calls are restricted to the superuser.

fhopen() opens the file referenced by fhp for reading and/or writing as specified by the argument flags and returns the file descriptor to the calling process. The flags are specified by or'ing together the flags used for the open(2) call. All said flags are valid except for O_CREAT.

fhstat(), fhstatfs(), and fhstatvfs() provide the functionality of the fstat(2), fstatfs(2), and fstatvfs(2), calls except that they return information for the file referred to by fhp rather than an open file.

RETURN VALUES
Upon successful completion, fhopen() returns the file descriptor for the opened file; otherwise the value -1 is returned and the global variable errno is set to indicate the error.

ERRORS
In addition to the errors returned by open(2), fstat(2), fstatfs(2), and fstatvfs(2) respectively, fhopen(), fhstat(), fhstatfs(), and fhstatvfs() will return

[EINVAL]
    Calling fhopen() with O_CREAT set.

[ESTALE]
    The file handle fhp is no longer valid.

SEE ALSO
fstat(2), fstatfs(2), fstatvfs(2), getfh(2), open(2)

HISTORY
The fhopen(), fhstat(), and fhstatfs() functions first appeared in DragonFly 1.1. The fhstatvfs() function first appeared in DragonFly 1.13.

AUTHORS
This man page was written by William Studenmund for NetBSD.