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FHOPEN(2) FreeBSD System Calls Manual FHOPEN(2)
NAME
fhopen, fhstat, fhstatfs - access file via file handle
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <sys/param.h>
#include <sys/mount.h>
#include <sys/stat.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);
DESCRIPTION
These system calls 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.
The fhopen() system call 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 argument is specified by
or'ing together the flags used for the open(2) system call. All said
flags are valid except for O_CREAT.
The fhstat() and fhstatfs() system calls provide the functionality of the
fstat(2) and fstatfs(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() and fhstatfs() 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), and fstatfs(2)
respectively, fhopen(), fhstat(), and fhstatfs() will return
[EINVAL] Calling fhopen() with O_CREAT set.
[ESTALE] The file handle fhp is no longer valid.
SEE ALSO
fstat(2), fstatfs(2), getfh(2), open(2)
HISTORY
The fhopen(), fhstat(), and fhstatfs() system calls first appeared in