get_nvectors (3) - Linux Manuals

get_nvectors: report the number of vector fields in a dirfile

NAME

get_nvectors --- report the number of vector fields in a dirfile

SYNOPSIS

#include <getdata.h>
unsigned int get_nvectors(DIRFILE *dirfile);

DESCRIPTION

The get_nvectors() function queries a dirfile(5) database specified by dirfile and returns the number of vector fields defined in the database (i.e. fields of types BIT,~LINCOM,~LINTERP,~MULTIPLY,~PHASE,~POLYNOM,~RAW, SBIT). Notably, this count does not include /META fields.

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

RETURN VALUE

Upon successful completion, get_nvectors() returns the number of vector fields in the dirfile. On error, it returns zero and sets the dirfile error to a non-zero error value. Possible error values are:
GD_E_BAD_DIRFILE
The supplied dirfile was invalid. The dirfile error may be retrieved by calling get_error(3). A descriptive error string for the last error encountered can be obtained from a call to get_error_string(3).