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.\" gd_naliases.3.  The gd_naliases 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_naliases 3 "25 December 2016" "Version 0.10.0" "GETDATA"

.SH NAME
gd_naliases \(em report the number of aliases of a field in a Dirfile

.SH SYNOPSIS
.SC
.B #include <getdata.h>
.HP
.BI "unsigned int gd_naliases(DIRFILE *" dirfile ", const char *" field_code );
.EC

.SH DESCRIPTION
The
.FN gd_naliases
function queries a dirfile(5) database specified by
.I dirfile
and counts the number of aliases of the entry (including the entry's name)
specified by
.IR field_code .

The
.I dirfile
argument must point to a valid DIRFILE object previously created by a call to
.F3 gd_open .

.SH RETURN VALUE
Upon successful completion,
.FN gd_naliases
returns an unsigned integer indicating the number of aliases of the specified
field code in the dirfile.  If successful, this count will be at least one.

On error, this function returns zero and stores a negative-valued error code in
the
.B DIRFILE
object which may be retrieved by a subsequent call to
.F3 gd_error .
Possible error codes are:
.DD GD_E_BAD_CODE
The supplied field code was not found in the database.
.DD GD_E_BAD_DIRFILE
The supplied dirfile was invalid.
.PP
A descriptive error string for the error may be obtained by calling
.F3 gd_error_string .

.SH HISTORY
The
.FN gd_naliases
function appeared in GetData-0.8.0.

.SH SEE ALSO
.F3 gd_aliases ,
.F3 gd_alias_target ,
.F3 gd_open ,
dirfile(5)