NAME

       gd_field_list — retrieve a list of fields in a dirfile

SYNOPSIS

       #include <getdata.h>

       const char **gd_field_list(DIRFILE *dirfile);

DESCRIPTION

       The  gd_field_list()  function queries a dirfile(5) database specified by dirfile and returns a read-only
       list of names of the all fields defined in the database.  Notably, this list does not include /META  sub‐
       fields.

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

       The  array  returned  will be de-allocated by a call to gd_close(3) and should not be de-allocated by the
       caller.  The list returned should not be assumed to be in any particular order.  The array is  terminated
       by a NULL pointer.  The number of strings in the array can be obtained from a call to gd_nfields(3).

       The  caller  may  not  modify any strings in the array, or the array itself.  Doing so may cause database
       corruption.  The pointer returned is guaranteed to be valid until gd_field_list() is called again on  the
       same DIRFILE object, or until the array is de-allocated by a call to gd_close(3).

RETURN VALUE

       Upon successful completion, gd_field_list() returns a pointer to an array of strings containing the names
       of  all  the fields defined in the dirfile database.  On error it returns NULL and sets the dirfile error
       to a non-zero error value.  Possible error values are:

       GD_E_ALLOC
               The library was unable to allocate memory.

       GD_E_BAD_DIRFILE
               The supplied dirfile was invalid.

       The dirfile error may be retrieved by calling gd_error(3).  A descriptive error string for the last error
       encountered can be obtained from a call to gd_error_string(3).

SEE ALSO

       dirfile(5), gd_cbopen(3), gd_error(3), gd_error_string(3),  gd_field_list_by_type(3),  gd_mfield_list(3),
       gd_nfields(3), gd_vector_list(3)

Version 0.7.0                                    15 October 2010                                gd_field_list(3)