xenial (3) gd_get_string.3.gz

NAME

       gd_get_string — retrieve a string from a dirfile database

SYNOPSIS

       #include <getdata.h>

       size_t gd_get_string(DIRFILE *dirfile, const char *field_code, size_t len, char *data_out);

DESCRIPTION

       The  gd_get_string()  function  queries  a dirfile(5) database specified by dirfile for the string scalar
       field_code, which should not contain a representation suffix.  The first len  characters  of  the  string
       scalar are stored in the user-supplied buffer data_out.

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

       If len equals zero, or if data_out equals NULL, no data will be copied to data_out, but the length of the
       string scalar will still be returned by gd_get_string().  Otherwise, the argument data_out must point  to
       a  valid memory location of sufficient size to hold at least len characters.  If the length of the string
       scalar is greater than len, data_out will not be NULL-terminated.

RETURN VALUE

       On success, gd_get_string() returns the actual length of  the  specified  string  scalar,  including  the
       trailing  NULL  character.   A return value greater than len indicates that the output string is not null
       terminated.

       On error, it returns 0 and sets the dirfile error to a non-zero value.  Possible error values are:

       GD_E_BAD_CODE
               The field specified by field_code was not found in the database.

       GD_E_BAD_DIRFILE
               An invalid dirfile was supplied.

       GD_E_BAD_FIELD_TYPE
               The supplied field_code referred to a field of type other than STRING.   The  caller  should  use
               gd_getdata(3), or gd_get_constant(3) instead.

       GD_E_BAD_TYPE
               An invalid return_type was specified.

       GD_E_INTERNAL_ERROR
               An internal error occurred in the library while trying to perform the task.  This indicates a bug
               in the library.  Please report the incident to the maintainer.

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

SEE ALSO

       dirfile(5), gd_open(3), gd_error(3), gd_error_string(3), gd_put_string(3)