FHOPEN(2) BSD System Calls Manual FHOPEN(2)NAME
fhopen, fhstat, fhstatfs, fhstatvfs — access file via file handle
LIBRARY
Standard C Library (libc, -lc)
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.
The fhstat(), fhstatfs(), and fhstatvfs() functions return the value 0 if
successful; 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[ESTALE] The file handle fhp is no longer valid.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 ALSOfstat(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.
BSD September 28, 2008 BSD
