FHOPEN(2) BSD System Calls Manual FHOPEN(2)NAME
fhopen, fhstat, fhstatfs — access file via file handle
Standard C Library (libc, -lc)
fhopen(const fhandle_t *fhp, int flags);
fhstat(const fhandle_t *fhp, struct stat *sb);
fhstatfs(const fhandle_t *fhp, struct statfs *buf);
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.
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.
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[ESTALE] The file handle fhp is no longer valid.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 ALSOfstat(2), fstatfs(2), getfh(2), open(2)HISTORY
The fhopen(), fhstat(), and fhstatfs() system calls first appeared in
NetBSD 1.5 and were adapted to FreeBSD 4.0 by Alfred Perlstein.
This manual page was written by William Studenmund for NetBSD.
BSD June 29, 1999 BSD