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.Dd August 5, 2009 .Dt FHOPEN 2 .Os .Sh NAME .Nm fhopen , .Nm fhstat , .Nm fhstatvfs , .Nm fhstatvfs1 .Nd access file via file handle .Sh LIBRARY .Lb libc .Sh SYNOPSIS n sys/types.h n sys/mount.h .Ft int .Fn fhopen "const void *fhp" "size_t fh_size" "int flags" n sys/stat.h .Ft int .Fn fhstat "const void *fhp" "size_t fh_size" "struct stat *sb" n sys/statvfs.h .Ft int .Fn fhstatvfs "const void *fhp" "size_t fh_size" "struct statvfs *buf" .Ft int .Fn fhstatvfs1 "const void *fhp" "size_t fh_size" "struct statvfs *buf" "int flags" .Sh DESCRIPTION These functions provide a means to access a file given the opaque file handle .Fa fhp and the size .Fa fh_size of the opaque object as returned by .Xr getfh 2 . As this method bypasses directory access restrictions, these calls are restricted to the superuser.
p .Fn fhopen opens the file referenced by .Fa fhp for reading and/or writing as specified by the argument .Fa flags and returns the file descriptor to the calling process. The .Fa flags are specified by .Em or Ns 'ing together the flags used for the .Xr open 2 call. All said flags are valid except for .Dv O_CREAT .
p .Fn fhstat , .Fn fhstatvfs , and .Fn fhstatvfs1 provide the functionality of the .Xr fstat 2 , .Xr fstatvfs 2 , and .Xr fstatvfs1 2 calls except that they return information for the file referred to by .Fa fhp rather than an open file. .Sh RETURN VALUES Upon successful completion, .Fn fhopen returns the file descriptor for the opened file, while .Fn fhstat , .Fn fhstatvfs , and .Fn fhstatvfs1 return 0. Otherwise, -1 is returned and .Va errno is set to indicate the error. .Sh ERRORS In addition to the errors returned by .Xr open 2 , .Xr fstat 2 , .Xr fstatvfs 2 , and .Xr fstatvfs1 2 , respectively, .Fn fhopen , .Fn fhstat , .Fn fhstatvfs , and .Fn fhstatvfs1 will return l -tag -width Er t Bq Er EINVAL Calling .Fn fhopen with .Dv O_CREAT set or invalid .Fa fh_size . t Bq Er ESTALE The file handle .Fa fhp is no longer valid. .El .Sh SEE ALSO .Xr fstat 2 , .Xr fstatvfs 2 , .Xr fstatvfs1 2 , .Xr getfh 2 , .Xr open 2 .Sh HISTORY The .Fn fhopen , and .Fn fhstat functions first appeared in .Nx 1.5 . The .Fn fhstatvfs function replaced .Fn fhstatfs in .Nx 3.0 .
Indexes created Sat Sep 20 22:09:52 GMT 2025