.\" gd_fragmentname.3.  The gd_fragmentname man page.
.\"
.\" Copyright (C) 2008, 2010 D. V. Wiebe
.\"
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.\"
.\" This file is part of the GetData project.
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.TH gd_fragmentname 3 "21 July 2010" "Version 0.7.0" "GETDATA"
.SH NAME
gd_fragmentname \(em retrieve a dirfile format specification fragment name
.SH SYNOPSIS
.B #include <getdata.h>
.HP
.nh
.ad l
.BI "const char* gd_fragmentname(const DIRFILE *" dirfile ", int " index );
.hy
.ad n
.SH DESCRIPTION
The
.BR gd_fragmentname ()
function queries a dirfile(5) database specified by
.I dirfile
and returns the filename of the format specification fragment indexed by the
non-negative
.IR index .

The 
.I dirfile
argument must point to a valid DIRFILE object previously created by a call to
.BR gd_open (3).

The fragment with
.I index
equal to zero is always the primary fragment for the database (the file called 
.B format
in the root dirfile directory).  The largest valid value of
.I index
is one less than the total number of fragments, which may be obtained from a
call to
.BR gd_nfragments (3).
.SH RETURN VALUE
Upon successful completion,
.BR gd_fragmentname ()
returns a pointer to a read-only character string containing the file name of
the specified fragment.  On error,
.BR gd_fragmentname ()
returns NULL and sets the dirfile error a non-zero error value.  Possible error
values are:
.TP 8
.B GD_E_BAD_DIRFILE
The supplied dirfile was invalid.
.TP
.B GD_E_BAD_INDEX
The supplied index was out of range.
.PP
The dirfile error may be retrieved by calling
.BR gd_error (3).
A descriptive error string for the last error encountered can be obtained from
a call to
.BR gd_error_string (3).

.SH SEE ALSO
.BR dirfile (5),
.BR gd_error (3),
.BR gd_error_string (3),
.BR gd_include (3),
.BR gd_nfragments (3),
.BR gd_open (3),
.BR gd_parent_fragment (3)