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.\" gd_parent_fragment.3.  The gd_parent_fragment man page.
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.\" This file is part of the GetData project.
.\"
.\" Permission is granted to copy, distribute and/or modify this document
.\" under the terms of the GNU Free Documentation License, Version 1.2 or
.\" any later version published by the Free Software Foundation; with no
.\" Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
.\" Texts.  A copy of the license is included in the `COPYING.DOC' file
.\" as part of this distribution.
.\"
.TH gd_parent_fragment 3 "25 December 2016" "Version 0.10.0" "GETDATA"

.SH NAME
gd_parent_fragment \(em retrieve the parent fragment of a fragment in a Dirfile

.SH SYNOPSIS
.SC
.B #include <getdata.h>
.HP
.BI "int gd_parent_fragment(DIRFILE *" dirfile ", int " fragment_index );
.EC

.SH DESCRIPTION
The
.FN gd_parent_fragment
function queries a dirfile(5) database specified by
.ARG dirfile
and returns the index of the fragment which contains the
.B INCLUDE
directive for the fragment indexed by
.ARG fragment_index .

Since the primary format specification fragment is not included in any other
fragment, passing zero for
.ARG fragment_index
will result in an error.

.SH RETURN VALUE
On success,
.FN gd_parent_fragment
returns the index of the specified fragment's parent.  On error,
.FN gd_parent_fragment
returns a negative-valued error code.  Possible error codes are:
.DD GD_E_BAD_DIRFILE
The supplied dirfile was invalid.
.DD GD_E_BAD_INDEX
The supplied index was out of range, or was equal to zero.
.PP
The error code is also stored in the
.B DIRFILE
object and may be retrieved after this function returns by calling
.F3 gd_error .
A descriptive error string for the error may be obtained by calling
.F3 gd_error_string .

.SH HISTORY
The
.FN get_parent_fragment
function appeared in GetData-0.5.0.

In GetData-0.7.0, this function was renamed to
.FN gd_parent_fragment .

In GetData-0.10.0, the error return from this function changed from -1 to a
negative-valued error code.

.SH SEE ALSO
dirfile(5),
.F3 gd_include ,
.F3 gd_open ,
.F3 gd_fragmentname ,
.F3 gd_nfragments