snd_pcm_hw_param_first(9) centos man page | unix.com

SND_PCM_HW_PARAM_FIR(9) 					      PCM API						   SND_PCM_HW_PARAM_FIR(9)

NAME
       snd_pcm_hw_param_first - refine config space and return minimum value

SYNOPSIS
       int snd_pcm_hw_param_first(struct snd_pcm_substream * pcm, struct snd_pcm_hw_params * params, snd_pcm_hw_param_t var, int * dir);

ARGUMENTS
       pcm
	   PCM instance

       params
	   the hw_params instance

       var
	   parameter to retrieve

       dir
	   pointer to the direction (-1,0,1) or NULL

DESCRIPTION
       Inside configuration space defined by params remove from var all values > minimum. Reduce configuration space accordingly.

RETURN
       The minimum, or a negative error code on failure.

COPYRIGHT
Kernel Hackers Manual 3.10					     June 2014						   SND_PCM_HW_PARAM_FIR(9)