[alsa-devel] Problems in writing test apps

[haoshun]

Hi:
      sorry,forget to add the subject right now...
      I'm confused by a problem when i modify a test application "alsa-lib-1.0.13/test/control.c".
      I wanna use the structure "snd_ctl_elem_value_t",but when i write like this:
             snd_ctl_elem_value_t aaa;
      there will be an error:
             storage size of 'aaa' isn't known
     while 
             snd_ctl_elem_value_t *aaa;
     makes no errors. But i can't change it directly such as:
             aaa->id=test_id ; //test_id is defined before
     cause it will bring an error:
             dereferencing pointer to incomplete type
     I think i should use the function like "snd_ctl_elem_info_set_id",but i just want to know why,i don't think it disobeys the C syntax.Is there something different in the ALSA making procedure?or Makefile?



haoshun
2008-04-03